lock

This subgroup bundles icons of padlocks, unlocked locks, keyholes with locks, and keys themselves. They are useful not only for referring to the physical act of locking or unlocking something, but also for abstract ideas such as privacy, security, encryption or restricted access in the digital world. In chats they quickly convey states like "safe," "open," "protected," or "confidential" without lengthy explanation. The variety of key designs even lends itself to fantasy storytelling, interior-design talk, or references to treasure hunts.