dotted decimal

Noun

 * 1)  A method of writing IP addresses where the value of each byte is given as a decimal number, and each byte separated by a dot.
 * 127.0.0.1 is the dotted decimal representation of the binary value 01111111000000000000000000000001, which is the address your computer uses to refer to itself.

Usage notes
This format can be used to represent any number. It is the defacto-standard human-readable representation for IPv4 addresses, but is also used in software-release version numbering (see dot release), library classification, and medicine.