It’s shorthand for pound weight. The form “ib” is actually an abbreviation of the Latin word libra, which could mean a pound. Itself a shortened form of the full expression above.
Shorthand is an abbreviated symbolic writing method that increases speed and brevity of writing as compared to longhand.
Shorthand was used more widely in the past, before the invention of recording and dictation machines.
How many types of shorthand are there? There are three types of shorthand used in the English Language.
Shorthand, also called stenography, a system for rapid writing that uses symbols or abbreviations for letters, words or phrases.
A system of fast writing that uses lines and symple signs to represent words and phrases.