Ukulele

The ukulele ( from the Hawaiian ʻukulele, pronounced ) is a musical instrument with four strings. It is also called the "uke" for short. Ukuleles are part of the guitar family of instruments. The strings are usually tuned G, C, E, A or A, D, F#, B. Ukuleles normally have nylon strings or gut strings. 
Ukuleles commonly come in four sizes: soprano, concert, tenor and baritone. Sopranino and bass ukuleles also exist. Sopraninos are tuned to standard tuning, however, baritone ukuleles are tuned to D, G, B, E (the top four strings of a guitar). Bass ukuleles are tuned E, A, D, G (bass guitar and double bass tuning).
The ukulele was invented in the 19th Century AD in Hawaii, where people got the idea from small guitar-like instruments known as cavaquinhos brought to the island by Portuguese sailors.