What format to save in?

What format do I save in for my objects to open in things like 3D Max & Maya Carrara etc as ive been savin in 3ds & Objects etc but people have said “doens open” or “opens but empty” Not many people seem to use Blender on the sites Im tryin to use.
PS praise to Blender for bein so User Friendly & Imaginative & FREE

You have to export your blender mesh and save it in a format those programs can read. Use the Export section/scripts http://wiki.blender.org/index.php/Manual/Bundled_Scripts#Export accessible within Blender via File->Export