Textual criticism is a branch of textual scholarship, philology, and literary criticism that is concerned with the identification of textual variants, or different versions, of either manuscripts (mss) or of printed books. Such texts may range in dates from the earliest writing in cuneiform, impressed on clay, for example, to multiple unpublished versions of a 21st-century author's work. Historically, scribes who were paid to copy documents may have been literate, but many were simply copyists, mimicking the shapes of letters without necessarily understanding what they meant. This means that unintentional alterations were common when copying manuscripts by hand. Intentional alterations may have been made as well, for example, the censoring of printed work for political, religious or cultural reasons. Additionally, interpolation, the insertion of new material into an existing text, can occur when scribes or editors added explanatory notes, corrections, or supplementary content that later became incorporated into the main text.
The objective of the textual critic's work is to provide a better understanding of the creation and historical transmission of the text and its variants. This understanding may lead to the production of a critical edition containing a scholarly curated text. If a scholar has several versions of a manuscript but no known original, then established methods of textual criticism can be used to seek to reconstruct the original text as closely as possible. The same methods can be used to reconstruct intermediate versions, or recensions, of a document's transcription history, depending on the number and quality of the text available.
