Patent US 4,136,395

Spelling errors in a word processing system are detected and presented to the operator for correction at the end of a document page. A dictionary memory contains representations of the correct spellings for words most frequently used. As each word is typed, it is stored in a word queue where it is compared to the contents of the dictionary memory. If the compare is unequal, then the word and its location on the page are stored in an error memory. When an end of page indicator is set the printer automatically repositions the print head at the ending character of the first word in the error list. When the operator keys in the correct spelling, the printer is caused to remove the misspelled word from the page and type the correct spelling. The corresponding word in the error memory is also corrected. As each misspelled word in the error memory is corrected, the remainder of the memory is scanned and repetitions of the same spelling error are automatically corrected.