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.
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 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.
I used to think that the web was one continuous conversation. I log in, and the website "remembers" me while I browse.
But the truth is, the web is stateless. Every time you click a link, it's like meeting the server for the first time. It has no idea who you are or what you did five seconds ago.
Cookies are the sticky notes that solve this problem.
I used to think that a "character" was just a "byte." If I had a string of 10 characters, it should be 10 bytes long.
That works fine if you only use the English alphabet. But the moment someone adds an emoji (like ⚡) or a character from another language, the math breaks.
Let's look at why character encoding is so confusing.
I used to use the words "concurrent" and "parallel" interchangeably. I thought they both just meant "doing more than one thing at the same time."
But in computer science, they have very specific meanings. As Rob Pike (one of the creators of Go) says: "Concurrency is about dealing with lots of things at once. Parallelism is about doing lots of things at once."
Let's look at how that works at my favorite coffee shop.
I used to think that "Internet Speed" was just one number. If I had 100 Mbps, everything should be fast, right?
But sometimes, even with a great connection, websites take forever to start loading, or my video calls stutter.
It turns out "speed" is actually two different things: Latency and Throughput.
I remember the first time I got "High Speed" internet. The box said 100 Mbps, but when I started downloading a game, Steam told me I was only getting 12 MB/s.
I felt cheated! Was the ISP lying? Did my router have a leak?
It turns out, they were both right. They were just measuring the same thing with two different rulers.
Have you ever wondered why your computer's storage space seems smaller than what was advertised? Part of the answer lies in how data size units like Kibibyte (KiB) and Kilobyte (KB) are defined. Although they sound similar, they represent different amounts of data — and knowing the difference can help you avoid confusion.