I used to think that when I formatted a USB drive or deleted a file, the data was physically wiped off the disk. I imagined a tiny magnet or a laser clearing the surface until it was blank again.
But then I learned that computers are lazy. When you delete something, the data is usually still there—the computer just pretends it isn't.
Let's look at why "deleting" is just a lie we tell ourselves.
I used to see the same numbers popping up in error logs, hex dumps, and config files.
255, 1024, 65535, 2147483647.
They felt like a secret code. If you know these numbers, you can start to guess what kind of bug you're looking at before you even read the code.
Let's look at the "Magic Numbers" of computing and why they keep appearing.
I used to think that when I downloaded a 1 GB file, it was sent as one giant chunk of data.
But it's actually sent as millions of tiny "envelopes" called packets. And almost every single one of those envelopes is exactly 1500 bytes long.
This is the MTU (Maximum Transmission Unit), and it’s one of the weirdest relics of the early internet.
I remember when I was first learning to code, I thought 0 and NULL were the same thing. They both mean "nothing," right?
But then I got my first NullPointerException (or a segmentation fault), and I realized that in computing, there is a massive difference between "the number zero" and "no value at all."
Let's look at why 0 is powerful, but NULL is dangerous.
I was looking at a bug report the other day where a user's "Join Date" was listed as December 31, 1969.
I knew they hadn't joined the app before the internet existed, so I knew exactly what happened: somewhere in our database, their join date was set to 0.
In the world of computers, 0 isn't just a number—it's January 1, 1970.
If you've ever needed to populate a database with dummy users, test a UI with long text strings, or generate thousands of mock transactions, you've probably reached for Faker.js. It's the go-to tool for generating massive amounts of realistic fake data in JavaScript and TypeScript.
But have you ever stopped to wonder how it actually works? Where do all those names, addresses, and credit card numbers come from? Let's peek under the hood and explore the mechanics of Faker.js.
The world of "Cloud Computing" is full of acronyms that sound like they were invented by a committee of robots. IaaS, PaaS, SaaS... what do they actually mean for you as a developer or a business owner?
The easiest way to understand them isn't through server diagrams, but through Pizza.
I download a lot of videos for offline reference. Usually, I use yt-dlp in the terminal. It works great. But recently I discovered VidBee, an open-source video downloader built by nexmoe.
I see this all the time in configuration files or old code: a password or an API key that looks like a bunch of gibberish, like SGVsbG8gV29ybGQ=.
"Oh, it's encrypted," someone might say.
But it’s not! It’s just Base64 encoded. Anyone with a terminal or a web browser can turn that gibberish back into plain text in about two seconds.
I remember the first time I set up an SSH key. I had to generate a "public" one and a "private" one. I knew I was supposed to keep the private one secret and share the public one, but I didn't really understand why it worked.
If someone has my public key, can't they just reverse-engineer it to get my private key?
The answer is asymmetric encryption, and it's a bit like a magic padlock.