on the link anchor text and URL difference before, first say what is the anchor text.
anchor text belongs to a hyperlink, because whether it is clickable text or click on the link, are all hyperlinks. In a broad range, click on the picture, mail and so on are all hyperlinks, but in the chain of this range, only the clickable text or web site called hyperlinks. A hyperlink can use target= "_blank" strong, changes its appearance, color, open etc..
and hyperlink hyperlink to text links can improve the probability to attract spider crawling, will increase the weight of the target site, and retains the possibility of filtering small, not easy to be deleted the benefits of greater than the possibility of some text links.