engine

• JavaScript engine

    1. V8 (Chrome, Node)
        It compiles JavaScript code into machine code at execution by implementing a JIT (Just-In-Time) compiler
    2. Rhino
    4. Nashorn
    3. SpiderMonkey -> ActionMonkey -> TraceMonkey -> JägerMonkey -> IonMonkey (Mozilla Firefox)
    4. Chakra (IE)
  

• web browser engine (sometimes called web layout engine or web rendering engine)

    1. Gecko (firefox)
    2. WebKit
    3. Blink (chrome, Opera) fork of WebKit.
    4. Trident (also known as MSHTML)
    5. EdgeHTML (IE) fork of Trident