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.
If you've ever built a website or run a database, you've used 127.0.0.1. It’s the universal address for "this computer right here."
But have you ever stopped to wonder why it's such a weird number? Why not 1.1.1.1 or 0.0.0.0? And why is the whole 127.x.x.x block reserved just for us?
It’s the classic interview question, but it’s also one of the most interesting ways to understand how the internet actually works.
When you type google.com and hit Enter, your browser goes on a massive scavenger hunt across the globe, all in a few hundred milliseconds.
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.