A link that doesn’t work anymore is called a dead link, broken link or dangling link.

Link rot (or linkrot) is the process by which the collection of links on a website gradually point to web pages or servers that have become permanently unavailable. The phrase also describes the effects of failing to update out-of-date web pages that clutter search engine results.

Because broken links are, to some, very annoying, generally disruptive to the user experience, and can live on for many years, sites containing them are regarded as unprofessional.

Causes

A link may become dead for several reasons: The most common result of a dead link is a 404 error, which indicates that the web server responded, but the specific page could not be found. Some news sites contribute to the link rot problem by keeping only recent news articles online where they are freely accessible at their original URLs, then removing them or moving them to a paid subscription area. This causes a heavy loss of supporting links in sites discussing newsworthy events and using news sites as references.

Another type of dead link occurs when the server that hosts the target page stops working or relocates to a new domain name. In this case the browser returns a DNS error but may also display a site unrelated to the content sought. This can occur when a domain name is allowed to lapse, and is subsequently reregistered by another party. Domain names acquired in this manner are attractive to those who wish to take advantage of the stream of unsuspecting surfers that will inflate hit counters and PageRanking.

Header Tags (H1, H2, H3…) Optimization is a part of using the header tag in the webpage while writing the HTML code. These are second most important onpage SEO factors that you can use to get better SERPs. Heading tags (H1 through to H6) are given more weight by search engines than regular body copy.

How to effectively use Header tags:

1. Use your Main keyword in H1 tag.
2. Try to keep the “Keyword” at first
3. Use H2 tags to break down the main topic
4. Never include more than one <h1> tag on a page.

Header Tags Syntax:

·   <h1> H1 Header Tag <h1>

·     <h2> H2 Header Tag <h2>

·       <h3> H3 Header Tag <h3>

·         <h4> H4 Header Tag <h4>

·         <h5> H5 Header Tag <h5>

·         <h6> H6 Header Tag <h6>

I am sure these are some hints about header tags that will help you with your SEO efforts:

Meta Tags describe the information inserted into the “Head” of the web pages. Meta tags are part of HTML tags. Title tags, heading tags, body tags, meta tags and alt tags. Meta tags play a very important role to rank a weg page in search engine. There are different types of meta tags used in SEO field.

Now lets have a look at the different types of meta tags which are mostly considered by most of the SEOs.

• <meta name = “robots” content = “NOODP”/>

This illustrates to all search engines NOT to duplicate the ODP (Open Directory Project) description but the description which  is located on your website.

At the place of robots you can place any search engine name like. Ex: googlebot.

• <meta name = “robots” content = “NOINDEX”/>

This informs all search engines not to crawling a web page.

• <meta name = “robots” content = “NOFOLLOW”/>

It means that the web page will be indexed but the out going link from this particular page dose not crawl.

• <meta name = “robots” content = “NOSNIPPET”/>

It will not show any result in search engine.

• <meta name = “robots” content = “NOARCHIEVE”/>

It will not store the cached pages.

• <meta name = “robots” content = “UNAVILABLE_AFTER[ date ]”/>

Search engine does not crawl that page after specified date.