A keyboard of reduced size is provided in which multiple characters are assigned to each of the primary keys. The selection of the characters to be assigned to each specific primary key is based on the touch typing rules associated with a specific standardized keyboard, preferably allowing at least three rows of keys to be reduced to a single row of keys. A disambiguating system is used to interpret which of the characters and/or symbols assigned to a particular key is intended, typically by applying a set of disambiguating rules to generated input sequences.