During collation it may be useful to align the text of several or all witnesses, that is to write their text in a txt-document with spaces so that the parts corresponding to one another are below one another. Compare the illustration below. Alternatively many editors use spread-sheets containing one word per cell to align their collations. There are software programs able to perform this task quite well today.
Fig. 1. An aligned collation from a medical text, currently being edited at the University of Zurich, displaying seven witnesses' text. Where words are missing they are replaced by blank space.
In other languages
DE: Alignment (there seems to be no German word in use)