'no littering' means throwing trash or garbage on the floor is prohibited.

What means do not litter?

Litter is trash laying around on the ground. The message on the trash bin do not litter is telling you not to trow your trash just anywhere, put it in the garbage can.

What is the purpose of do not litter sign?

The purpose of the NO LITTERING sign is to remind road users not to litter and to inform them of the consequences of doing so.