Different kinds of computers use different conventions for the ordering of bytes within a word. Some computers put the most significant byte within a word first (this is called “big-endian” order), and others put it last (“little-endian” order).
So that machines with different byte order conventions can communicate, the Internet protocols specify a canonical byte order convention for data transmitted over the network. This is known as network byte order i.e. lower bytes is sent first then higher bytes.
htons() Host to Network Short
htonl() Host to Network Long
ntohl() Network to Host Long
ntohs() Network to Host Short