Understanding the CPU
The CPU, or Central Processing Unit, is often called the "brain" of the computer. This lesson looks at what it actually does.
What You'll Learn
- What the CPU does
- Why it's often called the "brain" of the computer
- How CPU cores affect performance
What the CPU Does
The CPU carries out the instructions given by whatever software is running. Every calculation, comparison, and decision a program makes happens because the CPU executes a stream of very small, precise instructions -- millions or billions of them every second.
CPU Speed and Cores
A CPU's speed affects how quickly it can execute instructions. Modern CPUs also have multiple "cores," which let them work on more than one task at the same time.
Example
A quad-core CPU has four cores, similar to having four workers instead of one -- it can genuinely work on four tasks in parallel rather than switching between them one at a time.
Key Concepts
Key Takeaways
- The CPU executes the instructions in every program you run
- More cores can let a computer handle more tasks at once
- CPU speed is one factor -- not the only one -- in how fast a computer feels
Knowledge Check
What is another common name for the CPU?