Difference between char , Varchar and nVarchar

Char DataType

Char datatype which is used to store fixed length of characters. 

Suppose if we declared char(50) it will allocates memory for 50 characters. 

Once we declare char(50) and insert only 10 characters of word 

then only 10 characters of memory will be used and other 40 characters of memory will be wasted.

varchar DataType

Varchar means variable characters and it is used to store non-unicode characters. 

It will allocate the memory based on number characters inserted. 

Suppose if we declared varchar(50) it will allocates memory of 0 characters 

at the time of declaration. Once we declare varchar(50) 

and insert only 10 characters of word it will allocate memory

 for only 10 characters.

nvarchar DataType

nvarchar datatype same as varchar datatype but only difference 

nvarchar is used to store Unicode characters and it allows you to 

store multiple languages in database. nvarchar datatype will take twice 

as much space to store extended set of characters as required by other languages.

So if we are not using other languages then it’s better to use 

varchar datatype instead of nvarchar