There are those that get on computer one night and find that all of their Web pages have disappeared from Google. While, others are still in search engine index, but don't rank high for nothing, not even for their Web site's name. It's a Web site owners worst nightmare, getting kicked out of search engines.
Ultimately, many webmasters had little or no warning that this was going to happen. Many webmasters are left with no idea why they were kicked out and are left wondering how to get back in Google's search engine. There could be any number of reasons why a Web site is banned by Google. The most common reasons for being banned are listed below in this article.
1. Duplicate Content This is when multiple Web pages have same content. Usually Google will just give a penalty to Web page for this, where page won't rank very high for keywords in that Web page, but there have been cases where complete Web sites were banned because they had to much duplicate content. You should make sure there is no other Web site using your content.
To check for duplicated content simply search with unique phrase on your Web page. If you find a Web site that has stolen your content you should contact site owner and tell them to take it down or face legal action. Also, for copyright violations visit www.google.com/dmca.html and notify them that someone is infringing on your site's copyright
2. Cloaking This is Web pages created just for search engines, where it delivers one version of a page to a Internet user and a different version to a search engine. Cloaking Web pages are created to do well for particular keywords. There are various ways to deliver cloaking Web pages. Each search engine's spider has an agent name, cloaked page is than only delivered to spider with user agent name that was chosen.
You can also deliver cloaked pages to search engines by IP address, but Google and other search engines say they can detect cloaking. There are other reasons to use cloaking, such as custom language delivery and geotargeted advertising.
3. Hidden text or hidden links This is text or a link that is invisible to naked eye on a Web page, but are seen by spiders. Search engines use to have a hard time spotting this technique, but now days you should avoid doing this because Google and other search engines can spot this easily. Even if a search engine doesn't spot your hidden link, a competitor might find it and report your site. Sometimes this can be done without even knowing, so you better double check each Web page that you have messed with in past few weeks.
4) Keyword stuffing Keyword Stuffing is when you load a Web page up with keywords in Meta tags or on Web page's content. The General techniques today for keyword stuffing are repeating same word(s) over and over again in Meta tags or on Web page's content or using invisible text, as we talked about up above in this article. If word is repeated to much it will raise a red flag to search engines and they likely will place a Spam filter on site.