Irvine Welsh is a Scottish novelist and short story writer, born on 27 September 1958. He gained widespread recognition for his 1993 novel Trainspotting, which was adapted into a critically acclaimed film. Welsh is also known for his work in theatre and film, having written plays and screenplays, and directed several short films.

His writing often explores the darker sides of human nature and drug use, set against the backdrop of his native Scotland. Welsh is celebrated for his depiction of anti-heroes and the underbelly of society, with characters that, despite their flaws, are portrayed with a humanistic depth that renders them relatable and sympathetic.

Welsh's work is characterized by the use of the Edinburgh Scots dialect, adding a unique flavor and challenge to readers who are not familiar with this style. His prose often features gritty depictions of life and complex human themes.