First, the search engine works
Search engines work is divided into three stages, namely crawling, indexing and retrieval
1, reptiles 
Search engines have web crawlers or spiders to crawl executed, each time crawler access to pages, it will copy the URL of the page and add it to the index.
In the "spider" crawls the web, refining keywords this process, there is a problem: "Spider" can understand. If your site is flash and js, then it is not read. Accordingly, if the site is its language, then it will be able to understand, it's the language that is SEO
2, index 
This stage, the crawler will create a search engine's index. Index like a giant book that contains a copy of each page of the reptiles found. If any page changes, the crawler will use the new content update your book
3, Search 
This search engine is to provide the most useful and relevant answers to the final stage of a particular order
Two, SEO Introduction
Full name: Search English Optimization, search engine optimization, that in order to enhance the number of pages indexed and ranking position in the search engine and natural search results do optimization.
1, SEO classification
- White Hat SEO: improvement and norms played a role in website design to make the site more friendly to search engines and users, and to earn a reasonable traffic from search engines
- Black Hat SEO: Search engine use and enlarge defect policy to get more traffic users
2, the use of white hat SEO
(1) the title of the website, keywords, description carefully chosen to reflect the positioning of the site, search engines understand what your site is doing;
(2) Web site content optimization: keyword corresponding content, increasing the density of keywords;
(3) a reasonable set Robot.txt files on the site;
(4) generates a site map for search engine friendly;
(5) increase the external links to each website promotion;
Third, the front-end SEO optimization
Through structural layout design and web site code optimization, making the front page not only allows browser users to read, but also allows "spider" read
1, site structure and layout optimization
(1) control the number of links Home
For small and medium business website, it is recommended within 100 homepage link, the linked nature can contain page navigation, bottom navigation, anchor text links, etc.
(2) flat directory hierarchy
Try to make "Spider" jump only three times, will be able to reach any page within the site within
(3) optimize navigation
Navigation should maximize the use of text mode, you can also navigate with pictures, but the <img> tag sure to add "alt" and "title" attribute to tell search engine positioning navigation
<img src="" alt="" title="">
Secondly, on each page should add breadcrumbs
For users, allows users to understand the current position is located, form a better sense of location, and user-friendly operation;
Spiders, being able to clearly understand the structure of the site, while also increasing the number of internal links, easy grab, lower bounce rate.
Specification (4) Structure Layout Optimization
a, head of the page: logo and main navigation, and user information
b, page body: left breadcrumbs and body; the right to put popular articles and related articles, not only enhance the relevance of the page, the page also enhance the right weight
c, bottom of the page: Copyright Information and Links
Note: page navigation Recommended wording: "12345678910 drop-down box / input box", such a "spider" jump directly according to page number, page jump directly select dropdown
Size (5) control of the page
A page should not exceed 100k, too, slow page loads, the user experience is not good, and once the timeout, "spider" will leave
2, page code optimization
（1）<title>
Title, stressed that the focus can, try to make each page < title > title of non-repetition
< Title > League of New Official Website - Tencent Games </ title >
（2）<meta keywords>
Key words, include important keywords to a few pages
< Meta name = "Keywords" Content = "League of Legends, lol, lol novice packs, lol Raiders, lol video, lol video Raiders, hero material, League of Legends War College, star commentary video, 101 War College, hero, Raiders, WCG , light icon, event " >
（3）<meta description>
Page description, high-level overview of web content keywords, each page should be different
< Meta name = "the Description" Content = "League official website, mass styles of heroes, rich and convenient item synthesis system, in-game matching, ranking and competitive system, original" Summoner "systems and skills, system combination runes, talent, etc., will take you into a new and colorful game world. " >
(4) semantic tags
For example: h1-h6 is a title type, < NAV > tag is used to set the main navigation page, and the like
(. 5) < A > tag:
In-page links, to add " title " attribute to illustrate, let visitors and "spiders" know;
External links, links to other sites, you need to add EL = " nofollow " After attribute to avoid "spider" climb external links, not back
(6) the title text use < h1 > tag:
"Spider" that it is the most important, if not like < h1 > default style set by CSS
（7）<br>
Wrap text content only for
< P > first line < br /> second line of text < br /> The third line of text </ P >
（8）<caption>
Tables should use < Caption > table header tag
(. 9) < IMG > should be used " Alt " attribute will be described
(10) < strong > and < EM >: use should be emphasized
< Strong > tag in the search engine to highlight Keywords
< EM > tag to emphasize the effect after the < strong >
And < B >, < I > tag: except for displaying the results, can not afford the effect of SEO
(11) avoid the use of & nbsp; and & copy;
Whitespace & nbsp; application to set CSS
Copyright symbol & copy; it can be used as the input method to fight "©"
(12) less iframe framework, because the "spider" generally do not read the contents of
(13) less display: none;
For not want to display the text, should be set z-index or provided to the outside of the browser display. Because the search engines will filter out display: none in content