Download types.c and compile (on Pyrite) types using gcc -ansi -o types types.c. By running ./types you will see the following output:

         unsigned char | 1 bytes |  8 bits |                    0 to                  255 | (0 to 2^8-1) 
    unsigned short int | 2 bytes | 16 bits |                    0 to                65535 | (0 to 2^16-1) 
          unsigned int | 4 bytes | 32 bits |                    0 to           4294967295 | (0 to 2^32-1) 
     unsigned long int | 8 bytes | 64 bits |                    0 to 18446744073709551615 | (0 to 2^64-1) 
unsigned long long int | 8 bytes | 64 bits |                    0 to 18446744073709551615 | (0 to 2^64-1) 
           signed char | 1 bytes |  8 bits |                 -128 to                  127 | (-2^7 to 2^7-1) 
      signed short int | 2 bytes | 16 bits |               -32768 to                32767 | (-2^15 to 2^15-1) 
            signed int | 4 bytes | 32 bits |          -2147483648 to           2147483647 | (-2^31 to 2^31-1) 
       signed long int | 8 bytes | 64 bits | -9223372036854775808 to  9223372036854775807 | (-2^63 to 2^63-1) 
  signed long long int | 8 bytes | 64 bits | -9223372036854775808 to  9223372036854775807 | (-2^63 to 2^63-1) 
                 float | 4 bytes | 32 bits | 12/10 = 1.20 : 1.20000004768371582031 
                double | 8 bytes | 64 bits | 12/10 = 1.20 : 1.19999999999999995559 

These define the sizes and ranges of the different primitive types in C on Pyrite. Ranges for float and double are difficult to describe, so look at the IEEE Floating Point Specification if you are interested.