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.
This is the Poster icon for Windows 10
. Here we go. Optimized for 32x32 px, these are the simplest icons in the line style. Downloadable formats are PNG and SVG, among others. Icons8 icon pack is unique in providing a huge number of icons designed by the same team of four designers who create the new icons every working day in the same style and with the same quality. Same cool as the Bat Face, huh.