Collation. Character-by-character comparison of two or more texts. Traditionally, the process by which editors isolate patterns of error that indicate transcriptional descent, to determine whether one or more texts is a copy made from an earlier and thus more reliable copy. Some twentieth-century editors have used the term to describe the process of visual comparison by which transcriptions, galleys, etc. are checked for error. With modern technology, the “compare” function in word-processing software performs this function by comparing the machine-readable versions of galleys and page proofs against each other.