Touch switches

Touch switches, or otherwise known by most of the community as Coins, are small circles which activate when Madeline touches them, hence the name. Touch switches are first introduced in Old Site's A-Side, but appear in a majority of the levels afterwards. When Madeline activates all of the Touch switches in a given room, it will unlock the exit, a given path, or simply move a block. There are many examples of this happening within the vanilla game, and especially so within mods.