Each programming language works differently with variables. Most of them allow any character string that is not "reserved" (that is, has a special meaning) to be the name of the variable. It is good in computer programming to use names that tells what will be stored in the variable (such as "person", "age", "total", and so on). Also, some languages like C and Java require the data type of the variable (that is, the kind of content that will be stored in it) to be declared (written) when the variable is created. Others, like Python and Visual Basic, do not have this rule, which allows the type of variable to be changed when a new value is stored in it.