Issue link: https://read.uberflip.com/i/1146286
139 We'd like to hear your suggestions for improving our indexes. Send email to index@oreilly.com. Index Numbers 204 No Content status code AOL, 113 300 Multiple Choices (based on Content-Type) status code, 76 301 Moved Permanently status code, 76 302 Moved Temporarily (a.k.a. Found) status code, 76 303 See Other (clarification of 302) status code, 76 304 Not Modified status code, 76, 90 304 responses, 8 305 Use Proxy status code, 76 306 status code (no longer used), 76 307 Temporary Redirect (clarification of 302) status code, 76 A Accept-Encoding, 33 ads, serving, 117 Ajax, 96–102 active requests, 98 caching examples, 99–102 Google Docs & Spreadsheets, 101 Yahoo! Mail, 99–101 defined, 97 far future Expires header, 102 optimizing requests, 99 passive requests, 98 relationship between Web 2.0, DHTML, and Ajax, 96 technologies behind, 98 Yahoo! UI (YUI) Connection Manager for Ajax, 98 Akamai Technologies, Inc., 19 Alias directive, 80, 81 Amazon CSS sprites, 108 Expires header, 107 percentage of time downloading, 4 performance recommendations, 107 (see also top 10 U.S. web sites) AOL 204 No Content status code, 113 beacons, 113 DNS lookups, 113 Expires header, 112 gzip, 113 HTTP requests, 110 percentage of time downloading, 4 performance recommendations, 110–113 scripts, 112 (see also top 10 U.S. web sites) Apache 1.3 mod_gzip module, 31 Apache 2.x mod_deflate module, 32 application web servers, proximity to users, 18 autoindexing, 80