Before software, code, or the internet, there is a physical object on your desk. This chapter presses the power button and follows what happens — the parts the machine is built from, what it means to run a program, and why, underneath everything, a computer only ever handles numbers.
4 topics
Everything else in this course — the operating system, code, the web, the cloud — runs on the physical machine you're about to look inside. So this is where we start: with the box itself, the moment you turn it on, and the handful of parts doing all the work.
Four topics build the picture. First, the sequence that unfolds when you press power. Then the three core parts every computer is made of, and the one mix-up between them that confuses almost everyone. Then what it actually means to "run" a program. And finally, the surprising fact that all of it — every photo, message, and song — is stored as nothing but 0s and 1s.
What this chapter uncovers — from the parts, to running, to the bits underneath
The parts
A computer is built from a few core pieces — the processor, memory, and storage — each doing a different job.
Running
An app sitting on the disk does nothing until it is loaded into memory and the processor starts following its instructions.
Underneath
Every photo, message, and song is stored as nothing but 0s and 1s — the only language the machine really speaks.