PORTABLE : A portable computer is a computer that is designed to be moved from one place to another (in other words, it is a computer that is portable). Portable computers, by their nature, are microcomputers. Early portables were unkindly referred to as "luggables," referring to their great size and weight (owing partly to the need to include a full-blown CRT monitor, as LCD technology was not yet mature). The term "luggable" is today used mainly when speaking of 17" and larger widescreen laptops.
ULTRAPORTABLE/SUBNOTEBOOK :A subnotebook is a small and lightweight portable computer, with most of the features of a standard notebook computer but smaller. The term is often applied to systems that run full versions of desktop operating systems such as Windows or Linux, rather than specialized software such as Windows CE, Palm OS or Maemo
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