Imagine you have a special box that can hold one toy car. This box is called an "erlang."
Now, let's say you have lots of toy cars and you want to put them in the erlang box. Every time you put one car in the box, it takes up one "unit" of space in the erlang box.
So if you put 10 toy cars in the erlang box, you've filled up 10 units of space in the box. If you put 5 more toy cars in the box, you've used up a total of 15 units of space in the erlang box.
In computer programming, erlang is used to measure how much space is being used by a program or a system. Just like putting toy cars in an erlang box, every action or function in a program uses up a certain amount of erlang units. By measuring how many erlang units a program is using, developers can make sure it's running smoothly and efficiently.