Central Processing Unit

CLASS: SSS Two

The Central Processing Unit

Brief History of the CPU

The fourth generation of computers started with the invention of the Microprocessor. The Microprocessor contains thousands of ICs. Ted Hoff produced the first microprocessor in 1971 for Intel.

Definition of the CPU

The Central Processing Unit (CPU), also known as the microchip or the microprocessor (or processor for short), is the electronic circuitry within a computer that carries out the instructions of a computer program. This is the brain or heart of the computer. The main objective of the CPU is to perform mathematical calculations on binary numbers. Most modern CPUs are microprocessors, meaning they are contained on a single integrated circuit (IC) chip. Some computers employ a multi-core processor, which is a single chip containing two or more CPUs called "cores."

Components of the Central Processing Unit

The central processing unit consists of two parts:

1. Control Unit (CU)
2. Arithmetic Logic Unit (ALU)

The Control Unit

The control unit is that part of the CPU that uses electrical signals to direct the entire computer system to carry out, or execute, stored program instructions. Like an orchestra leader, the control unit does not execute program instructions; rather, it directs other parts of the system to do so. The control unit must communicate with both the arithmetic/logic unit and memory.

Functions of the Control Unit

• It activates the appropriate circuits necessary for inputs and output devices.
• It causes the entire computer system to operate in an automatic manner.
• It directs the system to execute instructions.
• It helps in communication between the memory and the arithmetic logical unit.
• It aids in the loading of data and instructions residing in the secondary memory to the main memory as required.

The Arithmetic Logic Unit (ALU)

This part of the CPU executes all arithmetic and logical operations. It is also defined as the part of the CPU that carries out arithmetic and logic operations on operands in a computer instruction.

Functions of the ALU

• The arithmetic and logic unit executes two main types of operations:
  • Arithmetic operations: These include addition, subtraction, multiplication, and division.
  • Logical operations: These compare data, such as numbers and characters, to test for conditions like greater than, less than, or equal to.

What is a Graphics Processing Unit (GPU)?

The Graphics Processing Unit (GPU) is a specialized electronic circuit designed to rapidly manipulate and alter memory to accelerate the creation of images, videos, and animations. While a CPU is the brain of a computer, the GPU is a powerful co-processor that handles the specific, high-volume calculations required for graphics and parallel tasks.

The Purpose of a GPU

The primary purpose of a GPU is to handle tasks that can be broken down into many smaller, independent calculations. This design, known as parallel processing, makes it exceptionally good at:

• Rendering complex 3D graphics for video games and virtual reality.
• Encoding and decoding video and animations.
• Performing scientific simulations and machine learning computations.
• Processing large datasets in data science and cryptography.

Key Differences between a CPU and a GPU

While both are processors, they are designed for different types of work. Think of it like this: a CPU is a brilliant general-purpose problem-solver, while a GPU is an expert at one very specific type of problem.

CPU (Central Processing Unit)	GPU (Graphics Processing Unit)
A few powerful, general-purpose cores	Thousands of smaller, more specialized cores
Sequential tasks	Parallel tasks
Latency (speed of a single task)	Throughput (speed of many tasks at once)

Diagrams

Figure 1: A photograph of a Central Processing Unit (CPU) chip.

Figure 2: A diagram showing the flow of data through the main components of the CPU.

Test Your Knowledge

Select the correct answer for each question and click 'Submit' to see your score.

1. Who produced the first microprocessor for Intel in 1971?

A) Bill Gates B) Steve Jobs C) Ted Hoff D) Charles Babbage

2. What is the main objective of the CPU?

A) To store long-term data. B) To perform mathematical calculations on binary numbers. C) To provide a user interface. D) To cool down the computer.

3. What are the two main components of the Central Processing Unit?

A) RAM and ROM B) Monitor and Keyboard C) Control Unit and Arithmetic Logic Unit D) Hard Drive and SSD

4. Which component of the CPU acts like an orchestra leader, directing other parts of the system?

A) The Arithmetic Logic Unit (ALU) B) The Cache Memory C) The Control Unit (CU) D) The Transistor

5. What is the primary function of the Arithmetic Logic Unit (ALU)?

A) To load data from secondary memory. B) To direct the flow of instructions. C) To perform arithmetic and logical operations. D) To activate input/output devices.

6. What is the primary reason a GPU is better suited for tasks like rendering 3D graphics compared to a CPU?

A) GPUs are more expensive. B) GPUs have fewer, more powerful cores. C) GPUs are designed for parallel processing with thousands of cores. D) GPUs are located on the motherboard.