How the case is bounded
Pattern, correspondence, and caution
The canonical Ripper series is generally treated as beginning with Mary Ann Nichols on August 31, 1888.
Elizabeth Stride and Catherine Eddowes were killed on the same night, forming the event traditionally called the Double Event.
The Dear Boss letter introduced the name Jack the Ripper into the case record and public mythology.
The authorship and authenticity of letters attributed to Jack the Ripper remain disputed.

