Puppy package manager is a tool for installing and un-installing packages.

PPM lets you select packages from online repositories. It will then download and install the software onto the system.
It can be accessed via-
Puppy Menu > Setup > Puppy Setup > Puppy Package Management

The PPM is also able to search and install dependencies when installing a packages. However, users have reported problems with packages that has too many dependencies.

Pet files
QuickPet - Install popular software on Puppy 5.2x Lucid
SlickPet - Install popular software on Puppy 5.3 Slacko
PPM page
PPM page on Barry's Blog