A term used to describe hardware that is small and lightweight, and can be battery powered for at least an hour. A portable computer is a computer small enough to carry. Portable computers include, ranging from largest to smallest, laptops, notebook and subnotebook computers, hand-held computers, palmtops, and PDAs.
An ambiguous term used to describe software has the ability to run on a variety of computers. Portable and machine independent mean the same thing; the software does not depend on a particular type of hardware. Java is a language that creates such software although there are other languages that do the same thing. The software may require compiling for a platform but the native code is the same.
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