Why is the computer beeps?

The following are some of the computer beeps:

1 short bipah:                           computer has booted right way
Two short bipah :                     CMOS error
1 long and 1 short bipah :         DRAM or logic board error
1 long and two short bipah:       graphics or monitor error
1 long and 3 short bipah:           keyboard errors
1 long and 9 short bips:             BIOS ROM error bipah
Long running bips:                     DRAM error
                 Error getting the short bipah

thanks