PureBasic comes with libs which are compiled to libs and they are closed source, so you cant fix a bug in a lib. Afaik freebasic comes with no precompiled libs and include the full source of the needed lib. So compilation time may take an eye blink longer but you can fix and extend existing libs. Btw, the stuff i saw over the years, PureBasic will be used mainly for Appz/GUI and FreeBasic more more Gfx things!? (I know only the FB related intros/demos/sources on this forum, so dont see what apps with GUI are coded in Freebasic on the other side)