14. The system of claim 10 , wherein: the interface is further configured to receive second information that describes a second input provided to the user interface of the application displaying the word processing document; and the user input processor is further configured to: identify a second type of command that is associated with the second input; append, in response to the second type of command being identified as a command to create a new paragraph at a second location in the word processing document, one or more characters that indicate a paragraph break to the end of the document buffer; and add, to the edit table, a second entry that correlates the paragraph break in the document buffer to the second location in the word processing document.
10. A system comprising: one or more computing devices; an interface of the one or more computing devices to receive first information that describes first input provided to a user interface of an application displaying a word processing document; a storage device accessible by the one or more computing devices to store a document buffer and an edit table that are associated with the word processing document, wherein the document buffer comprises text of the word processing document in a chronological order and the edit table comprises entries that correlate portions of text from the document buffer to locations in the word processing document; and a user input processor of the one or more computing devices to: identify a first type of command that is associated with the first input; append, in response to the first type of command being identified as a command to add textual content to a first location in the word processing document, the textual content to an end of the document buffer; add, to the edit table, a first entry that correlates the textual content in the document buffer to the first location in the word processing document; and provide an indication that the document buffer and the edit table have been updated to include the textual content.