Computer Languages History - Timeline chart, 1954 to today, printable; links to homes of many languages. Wikipedia: PL/I - An encyclopedia description of PL/I history with many links to programming terms. O'Reilly: The History of Programming Languages - A poster plots over 50 programming languages on a multi-layered, color-coded timeline. The Retrocomputing Museum - Dedicated to programs that induce sensations that hover somewhere between nostalgia and nausea. The freaks, jokes, and fossils of computing history. Diagram of Languages - Two diagrams showing how many languages are related to each other. Historic Documents in Computer Science - Original, historic first documents for many early programming languages, like language manualsa, scanned and converted to PDF form.