Computer: 5 Things You Should Know

Question: ENIAC, an early 1940s computer, filled a whole room. Why can a phone today hold far more computing power in your pocket?

Answer: Computers shrank because transistors, which are tiny electronic switches, replaced room-filling vacuum tubes. Today a single chip can hold billions of them.

Question: Every photo, song, and message on a computer is stored using only 1s and 0s. Why do computers use just two digits?

Answer: Each transistor is a switch that is either on or off, so computers count in binary. Long strings of 1s and 0s can represent any number, letter, color, or sound.

Question: A computer’s CPU, or processor, only does very simple math. How can it still run complex games and videos so smoothly?

Answer: A CPU breaks every task into tiny steps and runs billions of them each second across several cores. For games and video, a graphics chip (GPU) handles much of the work.

Question: The same laptop can edit photos, play games, and write essays without changing any parts. What lets one machine do so many jobs?

Answer: Hardware is the physical machine, and software is the set of instructions telling it what to do. Swapping programs lets one computer become a calculator, a studio, or a game console.

Question: In 1969, four university computers were linked in a network called ARPANET. What did that network eventually grow into?

Answer: ARPANET was a US research project that let distant computers share information. It grew into the internet, turning computers from solo calculators into tools for global communication.