Data Variable Types:

Array: A collection of two or more variables of the same type grouped
together. Each separate slot in the array is called an "array element", and
the elements are referenced within the array by an "array subscript", which
is a number identifying which cell in the array you wish to access.

Boolean: A variable that can only be true or false; It has no other possible
states.

Character: A variable that holds an ASCII text character.

Class: C++'s term for a structure.

Integer: A whole number which cannot have a decimal after it. If an operation
is performed on an integer variable which would make it decimalized, it will
be rounded to the nearest whole number. As opposed to real number.

Pointer: A variable that holds a memory address. In C, pointers are indicated
by preceding the variable name with an asterisk.

Real number: A number which can have a decimal after it.

Reference: A variation on the pointer which exists in C++, but not C.

Short/Long: This simply refers to how large the number in the variable can
be. Longer variables mean more storage space, which mean larger possible
numbers.

Signed/unsigned: A signed variable can be either positive or negative. An
unsigned variable is always positive.

String: A string of characters. In C, strings are actually stored as an array
of character-type variables, with each character being one element in the
array.

Structure: Not really a separate variable type in itself, a structure is
actually a collection of other variables grouped into a logical unit. For
example, a "person" structure might contain a person's name (string), their
age (integer), and bank balance (real number). These three variables could be
collectively grouped into a structure called "person".

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