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Introduction to Computer Architecture

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Main Functions of a Computer

There are four main functions of a computer that make user interaction possible:

  • Input
  • Processing
  • Memory
  • Output
- Input is data we give to our computers through interactions
- Processing is comprised of the translation of input and the instructions given for output
- Memory is used to store either temporary or permanent information
- Output is the information that gets returned by the computer

Computer Instructions

Computer instructions are written in binary, also known as machine code. Computer hardware operates on a series of these binary instructions through pulsating power signals that signify either OFF or ON based on the binary digits 0 and 1 respectively.

Binary Numbering System

The binary numbering system is built on a base of 2. Every time we reach a power of 2, we add another digit. The decimal system works the same way, just with 10.

Counting to 10 in binary:
Decimal Binary
0 0
1 1
2 10
3 11
4 100
5 101
6 110
7 111
8 1000
9 1001
10 1010

Least and Most Significant Bits (LSBs and MSBs)

The Least Significant Bit (LSB) is the farthest right digit in a binary number while the Most Significant Bit (MSB) is the leftmost digit. 0 is an acceptable value for both the MSB and the LSB.

8675309 expressed in Binary:
100001000101111111101101
^ ^
MSB LSB

Binary Data

Binary data is any set of expressions that result in a response set of only two answers.

Binary Data Examples:
- TRUE or FALSE
- ON or OFF
- 0 or 1
- LEFT or RIGHT
Non-Binary Data Examples:
- TRUE/FALSE/MAYBE
- LEFT/RIGHT/CENTER
- Ages of coworkers