A basha is a waterproof canvas or plastic sheet with eyelets or loops on the perimeter, which is used in camping, outdoor, or military situations to act as a shelter, in the form of an impromptu tent and/or groundsheet, usually supported with rope or even bungee cords attached to trees.
They are lightweight and can be put up rapidly, and camouflaged simply with foliage specific to the area of operation.
Because they are nearly invisible if well camouflaged, they are ideal for forming covert observation posts.
[2][3] The Assamese word refers to a range of naturally fabricated shelters made of bamboo and palm materials, but it most probably first entered British Army vocabulary to mean a temporary shelter by Chindits operating behind enemy lines in Burma, with the sheet taking its name from this usage.
Wider usage and adoption then came during the Malayan Campaign (1950–1959) where many ex-Chindits were recruited to fight the communist insurgents in the jungles.