Spelling, a basic component of information technology, has been investigated for its efficiency as a means of communication, with some researchers claiming that English spelling is close to ideal for really literate people to read fast and efficiently. Evidence about human abilities to obtain meaning from the printed word has come from studies of how beginners tend to spell, lists of the most common spelling errors, trends in popular choice of spelling, international vocabularies, and educational research. In reading, literate adults switch spelling sets automatically according to changes in the medium--print or handwriting, upper or lower case, and if bilingual, different sets of sound-symbol relationships. Studies have explored a variety of hypotheses about how present spelling might be made more accessible to a wider range of users. For example, experiments in surplus spelling have explored the notion of identifying and removing "clutter" in words--finding by experiment the letters that are not missed and that serve no purpose. Investigations have also revealed how few algorithms might be sufficient to modify present English spelling without effectively disguising it; only a few consistent rules might be needed to show morphemes and grammatical markers more clearly, while enhancing accurate phonological representation at the same time. Such studies can help to determine the "optimum" features of an orthography to match a particular language and suit the varied needs and abilities of its users. (HOD)