Computer architecture forms the backbone of computer science. So, it comes as no surprise it’s one of the most researched fields of computing.


But what is computer architecture, and why does it matter?


Basically, computer architecture dictates every aspect of a computer’s functioning, from how it stores data to what it displays on the interface. Not to mention how the hardware and software components connect and interact.


With this in mind, it isn’t difficult to realize the importance of this structure. In fact, computer scientists did this even before they knew what to call it. The first documented computer architecture can be traced back to 1936, 23 years before the term “architecture” was first used when describing a computer. Lyle R. Johnson, an IBM senior staff member, had this honor, realizing that the word organization just doesn’t cut it.


Now that you know why you should care about it, let’s define computer architecture in more detail and outline everything you need to know about it.


Basic Components of Computer Architecture


Computer architecture is an elaborate system where each component has its place and function. You’re probably familiar with some of the basic computer architecture components, such as the CPU and memory. But do you know how those components work together? If not, we’ve got you covered.


Central Processing Unit (CPU)


The central processing unit (CPU) is at the core of any computer architecture. This hardware component only needs instructions written as binary bits to control all its surrounding components.


Think of the CPU as the conductor in an orchestra. Without the conductor, the choir is still there, but they’re waiting for instructions.


Without a functioning CPU, the other components are still there, but there’s no computing.


That’s why the CPU’s components are so important.


Arithmetic Logic Unit (ALU)


Since the binary bits used as instructions by the CPU are numbers, the unit needs an arithmetic component to manipulate them.


That’s where the arithmetic logic unit, or ALU, comes into play.


The ALU is the one that receives the binary bits. Then, it performs an operation on one or more of them. The most common operations include addition, subtraction, AND, OR, and NOT.


Control Unit (CU)


As the name suggests, the control unit (CU) controls all the components of basic computer architecture. It transfers data to and from the ALU, thus dictating how each component behaves.


Registers


Registers are the storage units used by the CPU to hold the current data the ALU is manipulating. Each CPU has a limited number of these registers. For this reason, they can only store a limited amount of data temporarily.


Memory


Storing data is the main purpose of the memory of a computer system. The data in question can be instructions issued by the CPU or larger amounts of permanent data. Either way, a computer’s memory is never empty.


Traditionally, this component can be broken into primary and secondary storage.


Primary Memory


Primary memory occupies a central position in a computer system. It’s the only memory unit that can communicate with the CPU directly. It stores only programs and data currently in use.


There are two types of primary memory:


  • RAM (Random Access Memory). In computer architecture, this is equivalent to short-term memory. RAM helps start the computer and only stores data as long as the machine is on and data is being used.
  • ROM (Read Only Memory). ROM stores the data used to operate the system. Due to the importance of this data, the ROM stores information even when you turn off the computer.

Secondary Memory


With secondary memory, or auxiliary memory, there’s room for larger amounts of data (which is also permanent). However, this also means that this memory is significantly slower than its primary counterpart.


When it comes to secondary memory, there’s no shortage of choices. There are magnetic discs (hard disk drives (HDDs) and solid-state drives (SSDs)) that provide fast access to stored data. And let’s not forget about optical discs (CD-ROMs and DVDs) that offer portable data storage.


Input/Output (I/O) Devices


The input/output devices allow humans to communicate with a computer. They do so by delivering or receiving data as necessary.


You’re more than likely familiar with the most widely used input devices – the keyboard and the mouse. When it comes to output devices, it’s pretty much the same. The monitor and printer are at the forefront.


Buses


When the CPU wants to communicate with other internal components, it relies on buses.


Data buses are physical signal lines that carry data. Most computer systems use three of these lines:


  • Data bus – Transmitting data from the CPU to memory and I/O devices and vice versa
  • Address bus – Carrying the address that points to the location the CPU wants to access
  • Control bus – Transferring control from one component to the other

Types of Computer Architecture


There’s more than one type of computer architecture. These types mostly share the same base components. However, the setup of these components is what makes them differ.


Von Neumann Architecture


The Von Neumann architecture was proposed by one of the originators of computer architecture as a concept, John Von Neumann. Most modern computers follow this computer architecture.


The Von Neumann architecture has several distinguishing characteristics:


  • All instructions are carried out sequentially.
  • It doesn’t differentiate between data and instruction. They’re stored in the same memory unit.
  • The CPU performs one operation at a time.

Since data and instructions are located in the same place, fetching them is simple and efficient. These two adjectives can describe working with the Von Neumann architecture in general, making it such a popular choice.


Still, there are some disadvantages to keep in mind. For starters, the CPU is often idle since it can only access one bus at a time. If an error causes a mix-up between data and instructions, you can lose important data. Also, defective programs sometimes fail to release memory, causing your computer to crash.


Harvard Architecture


Harvard architecture was named after the famed university. Or, to be more precise, after an IBM computer called “Harvard Mark I” located at the university.


The main difference between this computer architecture and the Von Neumann model is that the Harvard architecture separates the data from the instructions. Accordingly, it allocates separate data, addresses, and control buses for the separate memories.


The biggest advantage of this setup is that the buses can fetch data concurrently, minimizing idle time. The separate buses also reduce the chance of data corruption.


However, this setup also requires a more complex architecture that can be challenging to develop and implement.


Modified Harvard Architecture


Today, only specialty computers use the pure form of Harvard architecture. As for other machines, a modified Harvard architecture does the trick. These modifications aim to soften the rigid separation between data and instructions.


RISC and CISC Architectures


When it comes to processor architecture, there are two primary approaches.


The CISC (Complex Instruction Set Computer) processors have a single processing unit and are pretty straightforward. They tackle one task at a time. As a result, they use less memory. However, they also need more time to complete an instruction.


Over time, the speed of these processors became a problem. This led to a processor redesign, resulting in the RISC architecture.


The new and improved RISC (Reduced Instruction Set Computer) processors feature larger registers and keep frequently used variables within the processor. Thanks to these handy functionalities, they can operate much more quickly.


Instruction Set Architecture (ISA)


Instruction set architecture (ISA) defines the instructions that the processor can read and act upon. This means ISA decides which software can be installed on a particular processor and how efficiently it can perform tasks.


There are three types of instruction set architecture. These types differ based on the placement of instructions, and their names are pretty self-explanatory. For stack-based ISA, the instructions are placed in the stack, a memory unit within the address register. The same principle applies for accumulator-based ISA (a type of register in the CPU) and register-based ISA (multiple registers within the system).


The register-based ISA is most commonly used in modern machines. You’ve probably heard of some of the most popular examples. For CISC architecture, there are x86 and MC68000. As for RISC, SPARC, MIPS, and ARM stand out.


Pipelining and Parallelism in Computer Architecture


In computer architecture, pipelining and parallelism are methods used to speed up processing.


Pipelining refers to overlapping multiple instructions and processing them simultaneously. This couldn’t be possible without a pipeline-like structure. Imagine a factory assembly line, and you’ll understand how pipelining works instantly.


This method significantly increases the number of processed instructions and comes in two types:


  • Instruction pipelines – Used for fixed-point multiplication, floating-point operations, and similar calculations
  • Arithmetic pipelines – Used for reading consecutive instructions from memory

Parallelism entails using multiple processors or cores to process data simultaneously. Thanks to this collaborative approach, large amounts of data can be processed quickly.


Computer architecture employs two types of parallelism:


  • Data parallelism – Executing the same task with multiple cores and different sets of data
  • Task parallelism – Performing different tasks with multiple cores and the same or different data

Multicore processors are crucial for increasing the efficiency of parallelism as a method.


Memory Hierarchy and Cache


In computer system architecture, memory hierarchy is essential for minimizing the time it takes to access the memory units. It refers to separating memory units based on their response times.


The most common memory hierarchy goes as follows:


  • Level 1: Processor registers
  • Level 2: Cache memory
  • Level 3: Primary memory
  • Level 4: Secondary memory

The cache memory is a small and fast memory located close to a processor core. The CPU uses it to reduce the time and energy needed to access data from the primary memory.


Cache memory can be further broken into levels.


  • L1 cache (the primary cache) – The fastest cache unit in the system
  • L2 cache (the secondary cache) – The slower but more spacious option than Level 1
  • L3 cache (a specialized cache) – The largest and the slowest cache in the system used to improve the performance of the first two levels

When it comes to determining where the data will be stored in the cache memory, three mapping techniques are employed:


  • Direct mapping – Each memory block is mapped to one pre-determined cache location
  • Associative mapping – Each memory block is mapped to a single location, but it can be any location
  • Set associative mapping – Each memory block is mapped to a subset of locations

The performance of cache memory directly impacts the overall performance of a computing system. The following cache replacement policies are used to better process big data applications:


  • FIFO (first in, first out) ­– The memory block first to enter the primary memory gets replaced first
  • LRU (least recently used) – The least recently used page is the first to be discarded
  • LFU (least frequently used) – The least frequently used element gets eliminated first

Input/Output (I/O) Systems


The input/output or I/O systems are designed to receive and send data to a computer. Without these processing systems, the computer wouldn’t be able to communicate with people and other systems and devices.


There are several types of I/O systems:


  • Programmed I/O – The CPU directly issues a command to the I/O module and waits for it to be executed
  • Interrupt-Driven I/O – The CPU moves on to other tasks after issuing a command to the I/O system
  • Direct Memory Access (DMA) – The data is transferred between the memory and I/O devices without passing through the CPU

There are three standard I/O interfaces used for physically connecting hardware devices to a computer:


  • Peripheral Component Interconnect (PCI)
  • Small Computer System Interface (SATA)
  • Universal Serial Bus (USB)

Power Consumption and Performance in Computer Architecture


Power consumption has become one of the most important considerations when designing modern computer architecture. Failing to consider this aspect leads to power dissipation. This, in turn, results in higher operating costs and a shorter lifespan for the machine.


For this reason, the following techniques for reducing power consumption are of utmost importance:


  • Dynamic Voltage and Frequency Scaling (DVFS) – Scaling down the voltage based on the required performance
  • Clock gating – Shutting off the clock signal when the circuit isn’t in use
  • Power gating – Shutting off the power to circuit blocks when they’re not in use

Besides power consumption, performance is another crucial consideration in computer architecture. The performance is measured as follows:


  • Instructions per second (IPS) – Measuring efficiency at any clock frequency
  • Floating-point operations per second (FLOPS) – Measuring the numerical computing performance
  • Benchmarks – Measuring how long the computer takes to complete a series of test programs

Emerging Trends in Computer Architecture


Computer architecture is continuously evolving to meet modern computing needs. Keep your eye out on these fascinating trends:


  • Quantum computing (relying on the laws of quantum mechanics to tackle complex computing problems)
  • Neuromorphic computing (modeling the computer architecture components on the human brain)
  • Optical computing (using photons instead of electrons in digital computation for higher performance)
  • 3D chip stacking (using 3D instead of 2D chips as they’re faster, take up less space, and require less power)

A One-Way Ticket to Computing Excellence


As you can tell, computer architecture directly affects your computer’s speed and performance. This launches it to the top of priorities when building this machine.


High-performance computers might’ve been nice-to-haves at some point. But in today’s digital age, they’ve undoubtedly become a need rather than a want.


In trying to keep up with this ever-changing landscape, computer architecture is continuously evolving. The end goal is to develop an ideal system in terms of speed, memory, and interconnection of components.


And judging by the current dominant trends in this field, that ideal system is right around the corner!

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OPIT Program Deep Dive: BSc in Computer Science
OPIT - Open Institute of Technology
OPIT - Open Institute of Technology
Feb 6, 2026 6 min read

Computer Science is fast becoming one of the most valuable fields of study, with high levels of demand and high-salaried career opportunities for successful graduates. If you’re looking for a flexible and rewarding way to hone your computing skills as part of a supportive global community, the BSc in Computer Science at the Open Institute of Technology (OPIT) could be the perfect next step.

Introducing the OPIT BSc in Computer Science

The OPIT BSc in Computer Science is a bachelor’s degree program that provides students with a comprehensive level of both theoretical and practical knowledge of all core areas of computer science. That includes the likes of programming, databases, cloud computing, software development, and artificial intelligence.

Like other programs at OPIT, the Computer Science BSc is delivered exclusively online, with a mixture of recorded and live content for students to engage with. Participants will enjoy the instruction of world-leading lecturers and professors from various fields, including software engineers at major tech brands and esteemed researchers, and will have many paths open to them upon graduation.

Graduates may, for example, seek to push on with their educational journeys, progressing on to a specialized master’s degree at OPIT, like the MSc in Digital Business and Innovation or the MSc in Responsible Artificial Intelligence. Or they could enter the working world in roles like software engineer, data scientist, web developer, app developer, or cybersecurity consultant.

The bullets below outline the key characteristics of this particular course:

  • Duration: Three years in total, spread across six terms.
  • Content: Core courses for the first four terms, a student-selected specialization for the fifth term, and a capstone project in the final term.
  • Focus: Developing detailed theoretical knowledge and practical skills across all core areas of modern computer science.
  • Format: Entirely online, with a mixture of live lessons and asynchronous content you can access 24/7 to learn at your own pace.
  • Assessment: Progressive assessments over the course of the program, along with a capstone project and dissertation, but no final exams.

What You’ll Learn

Students enrolled in the BSc in Computer Science course at OPIT will enjoy comprehensive instruction in the increasingly diverse sectors that fall under the umbrella of computer science today. That includes a close look at emerging technologies, like AI and machine learning, as well as introductions to the fundamental skills involved in designing and developing pieces of software.

The first four terms are the same for all students. These will include introductions to software engineering, computer security, and cloud computing infrastructure, as well as courses focusing on the core skills that computer scientists invariably need in their careers, like project management, quality assurance, and technical English.

For the fifth term, students will have a choice. They can select five electives from a pool of 27, or select one field to specialize in from a group of five. You may choose to specialize in all things cybersecurity, for example, and learn about emerging cyber threats. Or you could focus more on specific elements of computer science that appeal to your interests and passions, such as game development.

Who It’s For

The BSc in Computer Science program can suit a whole range of prospective applicants and should appeal to anyone with an interest or passion for computing and a desire to pursue a professional career in this field. Whether you’re seeking to enter the world of software development, user experience design, data science, or another related sector, this is the course to consider.

In addition, thanks to OPIT’s engaging, flexible, and exclusively online teaching and learning systems, this course can appeal to people from all over the globe, of different ages, and from different walks of life. It’s equally suitable for recent high school graduates with dreams of making their own apps to seasoned professionals looking to broaden their knowledge or transition to a different career.

The Value of the BSc in Computer Science Course at OPIT

Plenty of universities and higher education establishments around the world offer degrees in computer science, but OPIT’s program stands out for several distinctive reasons.

Firstly, as previously touched upon, all OPIT courses are delivered online. Students have a schedule of live lessons to attend, but can also access recorded content and digital learning resources as and when they choose. This offers an unparalleled level of freedom and flexibility compared to more conventional educational institutions, putting students in the driving seat and letting them learn at their own pace.

OPIT also aims not merely to impart knowledge through lectures and teaching, but to actually help students gain the practical skills they need to take the next logical steps in their education or career. In other words, studying at OPIT isn’t simply about memorizing facts and paragraphs of text; it’s about learning how to apply the knowledge you gain in real-world settings.

OPIT students also enjoy the unique benefits of a global community of like-minded students and world-leading professors. Here, distance is no barrier, and while students and teachers may come from completely different corners of the globe, all are made to feel welcome and heard. Students can reach out to their lecturers when they feel the need for guidance, answers, and advice.

Other benefits of studying with OPIT include:

  • Networking opportunities and events, like career fairs, where you can meet and speak with representatives from some of the world’s biggest tech brands
  • Consistent support systems from start to finish of your educational journey in the form of mentorships and more
  • Helpful tools to expedite your education, like the OPIT AI Copilot, which provides personalized study support

Entry Requirements and Fees

To enroll in the OPIT BSc in Computer Science and take your next steps towards a thrilling and fulfilling career in this field, you’ll need to meet some simple criteria. Unlike other educational institutions, which can impose strict and seemingly unattainable requirements on their applicants, OPIT aims to make tech education more accessible. As a result, aspiring students will require:

  • A higher secondary school leaving certificate at EQF Level 4, or equivalent
  • B2-level English proficiency, or higher

Naturally, applicants should also have a passion for computer science and a willingness to study, learn, and make the most of the resources, community, and support systems provided by the institute.

In addition, if you happen to have relevant work experience or educational achievements, you may be able to use these to skip certain modules or even entire terms and obtain your degree sooner. OPIT offers a comprehensive credit transfer program, which you can learn more about during the application process.

Regarding fees, OPIT also stands out from the crowd compared to conventional educational institutions, offering affordable rates to make higher tech education more accessible. There are early bird discounts, scholarship opportunities, and even the option to pay either on a term-by-term basis or a one-off up-front fee.

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OPIT Program Deep Dive: Foundation Year
OPIT - Open Institute of Technology
OPIT - Open Institute of Technology
Feb 6, 2026 6 min read

The Open Institute of Technology (OPIT) provides a curated collection of courses for students at every stage of their learning journey, including those who are just starting. For aspiring tech leaders and those who don’t quite feel ready to dive directly into a bachelor’s degree, there’s the OPIT Foundation Program. It’s the perfect starting point to gain core skills, boost confidence, and build a solid base for success.

Introducing the OPIT Foundation Year Program

As the name implies, OPIT’s Foundation Program is about foundation-level knowledge and skills. It’s the only pre-bachelor program in the OPIT lineup, and successful students on this 60-ECTS credit course will obtain a Pre-Tertiary Certificate in Information Technology upon its completion. From there, they can move on to higher levels of learning, like a Bachelor’s in Digital Business or Modern Computer Science.

In other words, the Foundation Program provides a gentle welcome into the world of higher technological education, while also serving as a springboard to help students achieve their long-term goals. By mixing both guided learning and independent study, it also prepares students for the EQF Level 4 experiences and challenges they’ll face once they enroll in a bachelor’s program in IT or a related field.

Here’s a quick breakdown of what the OPIT Foundation Program course involves:

  • Duration: Six months, split into two terms, with each term lasting 13 weeks
  • Content: Three courses per term, with each one worth 10 ECTS credits, for a total of 60
  • Focus: Core skills, like mathematics, English, and introductory-level computing
  • Format: Video lectures, independent learning, live sessions, and digital resources (e-books, etc.)
  • Assessment: Two to three assessments over the course of the program

What You’ll Learn

The OPIT Foundation Program doesn’t intensely focus on any one particular topic, nor does it thrust onto you the more advanced, complicated aspects of technological education you would find in a bachelor’s or master’s program. Instead, it largely keeps things simple, focusing on the basic building blocks of knowledge and core skills so that students feel comfortable taking the next steps in their studies.

It includes the following courses, spread out across two terms:

  • Academic Skills
  • Mathematics Literacy I
  • Mathematics Literacy II
  • Internet and Digital Technology
  • Academic Reading, Writing, and Communication
  • Introduction to Computer Hardware and Software

Encompassing foundational-level lessons in digital business, computer science, and computer literacy, the Foundation Program produces graduates with a commanding knowledge of common operating systems. Exploring reading and writing, it also helps students master the art of communicating their ideas and responses in clear, academic English.

Who It’s For

The Foundation Year program is for people who are eager to enter the world of technology and eventually pursue a bachelor’s or higher level of education in this field, but feel they need more preparation. It’s for the people who want to work on their core skills and knowledge before progressing to more advanced topics, so that they don’t feel lost or left behind later on.

It can appeal to anyone with a high school-level education and ambitions of pushing themselves further, and to anyone who wants to work in fields like computer science, digital business, and artificial intelligence (AI). You don’t need extensive experience or qualifications to get started (more on that below); just a passion for tech and the motivation to learn.

The Value of the Foundation Program

With technology playing an increasingly integral role in the world today, millions of students want to develop their tech knowledge and skills. The problem is that technology-oriented degree courses can sometimes feel a little too complex or even inaccessible, especially for those who may not have had the most conventional educational journeys in the past.

While so many colleges and universities around the world simply expect students to show up with the relevant skills and knowledge to dive right into degree programs, OPIT understands that some students need a helping hand. That’s where the Foundation Program comes in – it’s the kind of course you won’t find at a typical university, aimed at bridging the gap between high school and higher education.

By progressing through the Foundation Program, students gain not just knowledge, but confidence. The entire course is aimed at eliminating uncertainty and unease. It imbues students with the skills and understanding they need to push onward, to believe in themselves, and to get more value from wherever their education takes them next.

On its own, this course won’t necessarily provide the qualifications you need to move straight into the job market, but it’s a vital stepping stone towards a degree. It also provides numerous other advantages that are unique to the OPIT community:

  • Online Learning: Enjoy the benefits of being able to learn at your own pace, from the comfort of home, without the costs and inconveniences associated with relocation, commuting, and so on.
  • Strong Support System: OPIT professors regularly check in with students and are on hand around the clock to answer queries and provide guidance.
  • Academic Leaders: The OPIT faculty is made up of some of the world’s sharpest minds, including tech company heads, experienced researchers, and even former education ministers.

Entry Requirements and Fees

Unlike OPIT’s other, more advanced courses, the Foundation Program is aimed at beginners, so it does not have particularly strict or complex entry requirements. It’s designed to be as accessible as possible, so that almost anyone can acquire the skills they need to pursue education and a career in technology. The main thing you’ll need is a desire to learn and improve your skills, but applicants should also possess:

  • English proficiency at level B2 or higher
  • A Secondary School Leaving Certificate, or equivalent

Regarding the fees, OPIT strives to lower the financial barrier of education that can be such a deterrent in conventional education around the world. The institute’s tuition fees are fairly and competitively priced, all-inclusive (without any hidden charges to worry about), and accessible for those working with different budgets.

Given that all resources and instruction are provided online, you can also save a lot of money on relocation and living costs when you study with OPIT. In addition, applicants have the option to pay either up front, with a 10% discount on the total, or on a per-term basis, allowing you to stretch the cost out over a longer period to ease the financial burden.

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