(adj.) (1) When used to describe hardware, portable means small and lightweight. A portable computer is a computer small enough to carry. Portable computers include notebook and subnotebook computers, hand-held computers, palmtops, and PDAs
(2) When used to describe software, portable means that the software has the ability to run on a variety of computers. Portable and machine independent mean the same thing-that the software does not depend on a particular type of hardware.