Puppy Linux was originally created by Barry Kauler in 2003, as a smaller, leaner version of Vector Linux.
From the beginning, the idea was to make a small, lean, yet complete edition of Linux distribution that was useful from the get-go: the downloaded ISO contains all the standard applications to handle usual computing needs: word processor, spreadsheet, and web browser.
Another central idea that the OS would work off as a Live-CD, but with support for “persistence” - that is, keep data between reboot sessions. This way, the Live-CD can be used as if it is a fully installed operating system. However, if user data is corrupted in any way, in a flick of a switch the persistence can be turned off and Puppy would boot in its pristine, Live-CD state.
Size has always been a major consideration. Linux of these early days did not have good hardware support, thus Linux machines tend to be older and more obsolete computers with older CPUs and little RAM and storage. Also, broadband internet was not popular yet back then - many users were still on dial-up which limited the download speed to 38Kbps. So conscious decision were made to choose software components which provides the maximum functionality at a given size; e.g. the choice of ROX Filer as the file manager (which has stuck until today).
