ELI5: computer networks

What is a computer network?

A computer network is when multiple computers are connected together so they can talk to each other and share things, just like how friends pass notes back and forth in a classroom [2]. Instead of each computer being alone, they work as a team to send messages, share files, and play games together [2].

Why do we need computer networks?

Without networks, each computer would be stuck by itself and couldn't share information with other computers [2]. Networks let you send an email to a friend, watch videos from the internet, or play online games with people across the world [3].

How do computers know where to send messages?

Computers use special addresses called IP addresses, kind of like home addresses on a street, so messages get delivered to the right computer [4]. The network figures out the fastest path for your message to travel, just like GPS finds the best route to drive somewhere [3].

What are the main types of computer networks?

Small networks connect computers in one building (like a school), while the internet connects billions of computers worldwide [2][5]. There are also medium networks that connect multiple buildings or cities together [2].