Forum Discussion: Problem solution in C.

Why we use "# (preprocessor directive)"?

We learned about variables, namespaces and datatypes in C in lesson 3.

We learned about variables, namespaces and datatypes in C in lesson 3.

We learned about variables, namespaces and datatypes in C in lesson 3.

We learned about variables, namespaces and datatypes in C in lesson 3.

We learned about variables, namespaces and datatypes.

We learned about variables, namespaces and datatypes in C programming through lesson 3.

We learned about variables, namespaces and datatypes in C in lesson 3.

We've learned about variables, namespaces and datatypes.

We've learned about variables, namespaces and datatypes

We learned about variables, namespaces and datatypes in C in lesson 3.

We learned about variables, namespaces and datatypes in C in lesson 3.

We have learned about variables, namespaces and datatypes

We learned about variables, namespaces and datatypes in C in lesson 3.

Variables: where we store value.
Datatypes variable: A variable must have a data type associated with it, for example, it can have data types like integer, decimal numbers, characters, etc.
Naming: A variable name can only have letters (both uppercase and lowercase letters), digits and underscore. The first letter of a variable should be either a letter or an underscore. There is no rule on how long a variable name (identifier) can be.
Reserved words: Often found in programming languages and macros, reserved words are terms or phrases appropriated for special use that may not be utilized in the creation of variable names. For example, "print" is a reserved word because it is a function in many languages to show text on the screen.