Variables
A computer would not be needed if it did not have the ability to store various information in its memory. In order to create more interesting programs, one must learn how to store information in a computer's memory. At the same time, we need to learn how to somehow access the memory cells of the computer in which we save something.
A variable is a location in computer memory that has a name and stores some value corresponding to the type.
The word "variable" tells us that its value can change during program execution. The name of a variable is called identifier (from the word identify - to distinguish one object from another).
Before naming variables, you must REMEMBER easy rules:
- Latin letters can be used in variable names
a...z, A...Z (lowercase and uppercase letters differ);< /li>
- numbers and underscores can be used
_ ;
- you can't start a variable name with a number!;
- You can't use spaces, punctuation, or arithmetic symbols;
- for a better understanding of the program and ease of development, it is desirable that you give "speaking" variable names.
The last rule is optional, but highly recommended. The use of single-letter variables complicates the developer's work, since you have to keep in mind what the variable is responsible for.
And if you use "speaking" variables, the name itself will say what we store in it.
For example, if we need to store some name, then we can store the name in the a variable, or in the name variable. The latter option is preferable.