Background
Between 31 August and 9 November 1888 five women were murdered in the impoverished London district of Whitechapel: Mary Ann Nichols, Annie Chapman, Elizabeth Stride, Catherine Eddowes and Mary Jane Kelly, the so-called 'canonical five'. The killer was never found. The name 'Jack the Ripper' comes from a letter to the press that was probably a hoax, possibly written by a journalist. The case exposed the poverty of the East End and the limits of police investigation; massive newspaper coverage turned the murderer into a legend, while the lives of the victims long faded into the background.
Sources: Encyclopaedia Britannica: Jack the Ripper · Wikipedia: Jack the Ripper