A system comprising: one or more processors; and program instructions for providing a user interface. Execution of the program instructions by the one or more processors causes the one or more processors to display a user interface comprising: an entry mechanism for entering an input comprising at least one character, symbol, numeral or punctuation mark; a typing pane configured to display the input entered via the entry mechanism; wherein, in response to selection of a prediction based on the input entered via the entry mechanism, the typing pane is configured to replace the input entered via the entry mechanism by the prediction; and an undo button, wherein in response to user selection of the undo button, the typing pane is configured to replace the selected prediction by the input entered via the entry mechanism.