1. Interruption generates an interrupt
    interrupt controller

  2. Typeahead
    processor
    do_IRO()
    handler()
    less delay: best: less than 10 ms
    cache: 1. used before 2. used predictive

  3. Http/Https:
    protocol
    IPV4: 256^4
    IPV6:

  4. DNS:
    nslookup www.google.com
    traceroute www.google.com
    port:
    443 https
    8080⁄80 http

  5. Seven Layers:
    connect with https:
    (7). Application Layer: https
    (6). Presentation
    (5). Session
    (4). Transport:
    tcp : find a road from a to b
    tcp：Three Interaction Protocol
    (3). Network: ip
    (2). Data Link: ethernet
    (1). Physical

  6. Server-side:
    node.js single thread, avoid context switching.
    Context switching would causes loss of cache, and eventually reduce efficiency.

  7. Render in browser:
    User interface
    Browser engine: data persistence(cookies, user information)
    Rendering engine:
    networking, js interpreter, ui backend
    DOM tree: parse html into DOM tree
    Style Rules: css parser
    render tree: website