This article is about the main point of shortened words and units formation. Creation and development, stages, role and meanings of abbreviations in the process of word-formation. Historical and chronological classification of graphical and lexical abbreviations, reasons of making words shorter and creation the new units is also discussed in the article. The permanent progress and diversity of lexical system of the English Language gives us a lot of material in order to explore the function of this type of word-formation in any certain stage of development. At the same time we may compare the functional charasteristic features of shortening at different levels.