- browser checks cache; if requested object is in cache and is fresh, skip to #9(浏览器检查缓存，若缓存中存储着要请求的内容，并且内容是最新的，直接跳转到第9步)
- browser asks OS for server's IP address(浏览器请求操作系统（OS）解析服务器的IP地址)
- OS makes a DNS lookup and replies the IP address to the browser(操作系统做DNS解析，查找并返回IP地址给浏览器)
- browser opens a TCP connection to server (this step is much more complex with HTTPS)(浏览器与服务器建立TCP连接（若使用的是https协议，连接过程会更加的复杂)
- browser sends the HTTP request through TCP connection(浏览器通过TCP连接发送http请求)
- browser receives HTTP response and may close the TCP connection, or reuse it for another request(浏览器接收到http相应后，关闭（断开）TCP连接或者利用TCP发送其他http请求)
- browser checks if the response is a redirect (3xx result status codes), authorization request (401), error (4xx and 5xx), etc.; these are handled differently from normal responses (2xx)(浏览器检测http相应是否是重定向（http状态码为3xx），授权相应（401），错误相应（4xx和5xx）等；浏览器对这些状态码的处理与正常的相应（2xx）是不同的)
- if cacheable, response is stored in cache(若可以被缓存，则将相应存储到缓存中)
- browser decodes response (e.g. if it's gzipped)(浏览器解压相应（比如页面被gzip压缩过）)
- browser determines what to do with response (e.g. is it a HTML page, is it an image, is it a sound clip?)(浏览器决定以什么样式的方式解析http相应（比如他可能是个html网页，可能是一张图片，或者可能是个音频短片等）)
- browser renders response, or offers a download dialog for unrecognized types(若相应的是浏览器不能解析的格式，则下载该文件；否则浏览器就解析相应)
从输入URL到页面加载完成的过程中都发生了什么
· 3 min read