3.1. Integer data type

We have discussed about integer numbers, about how to perform simple operations and how to use variables to work with changing data.

Now it's time to see more details. For example, a "int" variable can store numbers up to about nine digits, both positive and negative, and occupies 4 bytes in memory.

(Note: If you do not know what a byte is, you should look at Appendix 1 of this text).

But it is not the only option. For instance, if we want a variable for a person's age, there is no need to use negative numbers, and 3 digits would be enough, so we can expect to find a more appropriate data type, which wastes less memory. There is also the opposite case: a bank may need to handle numbers with more than 9 digits, so an "int" would not be a good choice. In fact, if we talk about currency values, we would also need to use decimals, but we'll leave that for the next section.