What is Spam Indexing?

In spam indexing the www (word wide web) pages are modified in such a way that their chances of being viewed are increased as this way their relevance is increased by using spam indexing. By these unethical hacking techniques these websites are able to increase their ranking in search engine optimization terms. For this reason modern search engines make modifications to their searching algorithms and try to avoid these web pages using the dirty way of spam indexing. There are a number of ways in which spam indexing is done. One of the ways for example is of using the keywords unnecessarily.