https://damanarora.netlify.app/tags/fundamentals/ Recent content in Fundamentals on Daman Arora Hugo -- gohugo.io Tue, 19 May 2026 12:00:00 +0000 https://damanarora.netlify.app/posts/inside-a-running-process/ Tue, 19 May 2026 12:00:00 +0000 https://damanarora.netlify.app/posts/inside-a-running-process/ The first post followed the chain from disk to CPU. This one goes deeper into what actually happens once a program is running: how its memory is laid out, how the OS keeps track of it, and how many programs share the machine at once. From passive to active A program sitting on the hard disk is a passive thing. Just saved instructions, doing nothing. The moment you run it, it becomes an active process living in RAM. https://damanarora.netlify.app/posts/how-computers-run-programs/ Tue, 19 May 2026 10:00:00 +0000 https://damanarora.netlify.app/posts/how-computers-run-programs/ Every time you open an app, a chain of hardware kicks into motion behind the scenes. This post follows that chain from the disk all the way to the CPU, one idea building on the last. 1. Why RAM is faster than a hard disk RAM is electronic. Data is fetched by sending electrical signals, almost instantly. A hard disk drive (HDD) is mechanical. It has spinning platters and a moving arm that must physically travel to the right spot before it can read.