When we use a variable in a program then we have to mention the type of data. This can be handled using data type in C. Followings are the msot commonly used data types in C.
| Keyword | Format Specifier | Size | Data Range |
| Char | %c | 1 Byte | -128 to +127 |
| int | %d | 2 Bytes | -32768 to +32767 |
| long int | %ld | 4 Bytes | -2131 to +231 |
| unsigned int | %u | 2 Bytes | 0 to 65535 |
| float | %f | 4 Bytes | -3.4e38 to +3.4e38 |
| double | %lf | 8 Bytes | -1.7e38 ot +1.7e38 |
| long double | %Lf | 12-16 Bytes | -3.4e38 to +3.4e38 |