Quote: indefinite undo and redo is the most important feature of a system [»vandA7_1988]

Quote: although conventional security concerns protection, an interactive system needs recovery tools, e.g., undo and restore damaged data [»bereG9_1982]

Quote: undoing, guarded buttons, and edit recovery provide confidence for rapid system interaction [»teitW3_1985]

Quote: every action should be reversible; in a car you don't undo the last turn, you turn the other way [»shneB_1985]

Quote: an complete snapshot of the Smalltalk environment can be taken at any time and later resumed [»teslL8_1981]

Quote: with reversible operations, execute immediately and redo if conflict [»sariS10_1985]

Quote: in debugging, need to general mechanism to remove side-effects so that operations can be reversed and initial states restored [»heerJ4_1985]

Quote: in debugging robots, it can be difficult or impossible to undo errors [»goldR_1985]

Quote: added reversible execution across multiple processes to Simula; particularly useful for debugging [»lafoF3_1984]

Quote: undo algorithm for bitmap-based collaborative graphics; reduce space cost; uses timestamps, state vector, and quadtrees [»wangX11_2002]

Quote: make delete reversible by moving deleted segments to a special file [»teitT6_1979]

Quote: implement 'undo' with an undo transcript, redo transcript, and sequence numbers; e.g., global substitution in reverse order [»pikeR1_1994]

Quote: undo a group edit by transposing the inverse operation to the original location in the history buffer [»sunC12_2000]

Quote: Concurrent Pascal includes a 'port' data type for undoing actions; invoked in error recovery [»shriSK12_1979]

Quote: Cornell_Program_Synthesizer can reverse execution for a bounded number of steps; with tracing and monitoring, allows quick convergence to error [»teitT9_1981]

Quote: erase and copy commands require confirmation with the effected region displayed; also undo [»goodM6_1981]

Quote: FRESS may be the first system with undo; it was the most popular feature [»vandA7_1988]

Quote: Guide expands or contracts buttons until document tailored to reader's needs [»browPJ11_1987]

Quote: Intermedia allows indefinite undo and redo upto last save point; makes users secure [»yankN1_1988]

Quote: instead of confirming a command, Smalltalk commands can be undone [»teslL8_1981]

Quote: Smalltalk's undo reverses effects of typing and backspacing up to the previous selection [»teslL8_1981]

Quote: 'cancel' in Smalltalk reverts to the last successfully compiled version of a method; 'undo' recovers your edits [»teslL8_1981]

Quote: ZStep allows a program to run forward or backward. It can step over graphical events