The anchor text, or hyperlink, is a clickable part of your text used usually to highlight your keyword and "attract" people to click on it.
So, how can anchor text help your link building effort? Anchor text is very important part of your campaign of building backlinks and with that in getting high position in search engines.
Search engines are getting the first information about site that you are linking to through this text.
Because many people realize importance of this text, they are putting their main keyword in this text.
However, there is a point where many of them are making a big mistake.
First rule of any link building strategy is that all of your efforts should look natural.
But people in most cases are using the same keyword as backlinking text in all their inbound links.
It will look definitely strange to Google and other search engines like Yahoo and Bing and it is a great possibility that your site will be penalized.
Therefore, you should diversify your text for backlinks if you want for your link building effort be successful.
You don't need to make different text for each backlink.
You should make a several versions of your anchor text and use them randomly.
For example, if your main keyword is "online business", your text versions should look like this: "online business"," business online"," learn business online"," learn online business" etc.
And also, it's very important that your anchor text is related to title of your web site.
That is the way to give, in search engines eyes, a credibility to your backlinks and web site.