JWM (Joe's Window Manager) is the default window manager in many Puppy Linux versions including Puppy4. It is light weight using only Xlib at a minimum.
See JWM Elements for information on how to use and configure.
The standard versions of Puppy 3, 4 and Puppy 5.3 Slacko use JWM as the default, Puppy 5.2x Lucid has JWM as alternative (select by using WMSwitcher).
JWM - use "JWM configuration"