Binary numbers are the life blood of computer.

You probably know what they look like: a bunch of 1’s and 0’s.

### Here are some **non-**examples of Binary numbers

- example 1 : 12
- example 2 : 31
- example 3 : 15

**Here are some examples of Binary numbers**

- example 1 : 101101
- example 2 : 101
- example 3 : 10

So how do you tell someone that your number is a binary Number?

I mean 10 could be a binary number or it could “ten”?

In fact, there’s a well known joke that goes like this :

There are 10 types of people in this world. Those that know binary numbers and those that do not

The entire premise of this joke is that “10” could be a binary number meaning ‘2’, but you would only know that if you understand how to convert binary numbers to decimal numbers.

Usually people write a subscript to indicate that a number is base 2 (binary) like this pictures:

So, that’s what Binary Numbers look like.

In the next post, we’ll talk about what it means to be a binary number (and how to convert binary numbers to ‘regular’ decimal numbers.)