What Is a Subnet Mask?

A subnet mask is something used in computer networks. It helps computers know which part of an address shows the network and which part shows the device. In simple words, it tells the computer, “These computers are close to you, and these others are far away.”

A subnet mask is useful when we want to break a big network into smaller groups. For example, a school might want one group for teachers and another for students. This makes it easier to manage and safer too. Each subnet mask looks like four numbers with dots, like an IP address.

Thanks to subnet masks, computers can send data faster and to the right place. They help networks work better and avoid confusion. Even if the word sounds difficult, subnet masks are very important in making the internet and other networks work well.