The Noun Project is a website launched in 2010 that aggregates and catalogs symbols that are created and uploaded by graphic designers around the world. Based in Los Angeles, the project functions both as a resource for people in search of typographic symbols and a design history of the genre.
The Noun Project’s mission is to share the world’s visual language. They collect and organize all the symbols that form languages into one easy-to-use online library that can be accessed by anyone. All the symbols on this site are completely free to download, and can be used for many different purposes, including presentations, vocabulary flashcards, etc.
Visit the project on: http://thenounproject.com/