What is a computer ?

  • A computer is a combination of 2 machines created by humans:

      1. A non-programmable computing machine that helps us perform calculations (+, -, *, /, etc.)

      2. A programmable non-computing machine that helps us perform tasks (e.g.: play a song)

                     

Non-programmable computing machines

  • A non-programmable computing machine is operated/controlled by humans to perform calculations (+, -, *, /, etc.)

          

  • Humans must manually enter the instructions into the computing machine one instruction at a time

Programmable non-computing machines

  • A programmable non-computing machine can perform a task according to instructions given in a program that can be altered

          

  • E.g.: a mechanical piano can play any song according to instructions given in a program sheet one row at a time

Programmable non-computing machines

  • A programmable non-computing machine can perform a task according to instructions given in a program that can be altered

          

  • E.g.: a mechanical loom can weive any pattern according to instructions given in a program sheet one row of threads at a time

    Here's a video on YouTube on mechanical weaving looms:

Computer: a programmable computing machine

  • A programmable computing machine can perform a series of computation according to instructions given in a program that can be altered

          

  • E.g.: a tax return computation program will make a computer calculate a person's tax return