# Variables

## int 

for storing integer

```c#
int age = 21;
```

## double

can store a decimal

```C#
double height = 300.5;
```

## bool

can store boolean
only true or false

```C#
bool alive = true;
```

## char

for a single carachter

```C#
char symbole = '@';
```

## String

don't forget the S in upper

```C#
String name = "Hello";
```

## constants

immutable values wich are known at compile time and 
do not change for th life of the program

just add the const keyword

```C#
const double pi = 3.14;
```

## Type casting

Converting a value to a different data type
Very useful because user input will always be strings

```C#
double a = 3.14;
int b= Convert.ToInt32(a);

int c= 123;
double d= Convert.ToDouble(c);

int e= 321;
String d= Convert.ToString(e);

String g = "$";
char h = Convert.ToChar(g);

String i = "true";
bool j = Convert.ToBoolean(i);
```

## GetType

Get the type of a variable

```C#
double a = 3.14;
Console.WriteLine(a.GetType())
```