PuTTY () is a free and open-source terminal emulator, serial console and network file transfer application. It supports several network protocols, including SCP, SSH, Telnet, rlogin, and raw socket connection. It can also connect to a serial port (since version 0.59). The name "PuTTY" has no definitive meaning.

Putty is a generic term for a material with high plasticity, similar in texture to clay or dough, typically used in domestic construction and repair as a sealant or filler. Painter's Putty is typically a linseed oil-based product used for filling holes, minor cracks and defacements in wood only. Putties can also be made intumescent, in which case they are used for firestopping as well as for padding of electrical outlet boxes in fire-resistance rated drywall assemblies. In the latter case, hydrates in the putty produce an endothermic reaction to mitigate heat transfer to the unexposed side.