Constants - Variables - Data Types

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There are 9 types of data types. These include boolean, string, integer, double, decimal, character, byte, float and long:

Boolean is a binary value, being either true or false.

bool example = true;

String is used for storing characters in word form.

string example = "hello world";

Integer is used to store whole numbers (32 bit values).

int example = 457568368;

Double is used to store numbers where there are numbers before and after the decimal point, using 64 bits of memory.

double example = 3.3;

Decimal is used to store larger numbers with information before and after the decimal point, using 128 bits of memory.

decimal example = 12.593;

Character is used to store single letters.

char example = 'A';

Byte is used to store a byte (eight bits). In C#, it is specifically an 8 bit integer (0-255).

byte example = 255;

Float is used to store a 32 bit decimal number, which must be defined as being a float using "F" or "f" to distinguish it from a double, or it may cause compilation errors.

float example = 9.4F;

Long integer is also used to store whole numbers (However these are 64 bit values).

long example = 7846354759340276482;

Constants are used to create a variable of a specified data type that can never be changed after declaration, all global variables should be declared constant. The only way to change it is to edit the code and re-compile.

const int example = 32