You must have heard of hidden links and wondered what they are, and why everyone seems to get so worked up about them? Fear not, I will explain. Basically, hidden links cannot be seen by the human eye (unless you have x-ray vision) but can be detected by search engine spiders as they crawl about the web looking for trouble. They usually come in the form of text that cannot be seen because it is written on the same colour as the background. Some links come in invisible CSS divs, others have been drastically reduced in size using CSS, so that they are extremely small, and some are linked periods in the middle of paragraphs. Using links such as these is not allowed and if you contravene this rule then you are violating Google's guidelines and putting yourself in danger of being banned from the search engines. Google is usually able to find most hidden links. While some techniques continue to work, it will not be long before the spiders detect them and you have serious problems. Paid links, are those that have been paid for by the linked site. Web developers use them to enhance their search engine rankings. They can be used to advertise and promote your site on a variety of other sites. However, Google is not very happy about paid links and is currently developing an algorithm to help them to detect and downgrade them. Recently, Google asked web developers to report paid links to the anti-spam team. All this information is very important for your web site. Any hidden elements should be removed immediately, or as soon as possible, before they are found and before your web site receives a serious ranking penalty. Paid links should not hurt you web site rankings at the moment, but neither will they help with the new algorithm change from Google. The most successful way to promote your Google rankings is to use inbound links. They are the kind of links that Google wants to encourage and they work hard to filter out the wrong kind. In order to succeed, you must be sure to play the search engine game with integrity. | 
