This icon is a part of a collection of Plakat flat icons produced by Icons8. Icons follow the guidelines of iOS, Windows, and Android and are designed by a single designer, guaranteeing the consistent quality. Both PNG and vector are available.
It's a logo of Poster reduced to a sheet of paper. The sheet of paper is slightly bent on the bottom right hand side and has a hole on the top. It looks like a normal poster you would see on a bulletin board.