Reciprocal Links For Your Site
Links help your popularity with the search engines. They should also bring you more visitors, if the sites that link to you are relevant, and have high traffic themselves.
The key word here is "relevant". Link farms and free-for-all link sites will probably reduce your ranking and visitor popularity if anything. After all, if you visit a fishing site, you probably won't be interested in links to baby food recipes, car maintenance, or knitting. That's the view the search engines take too - it's not the quantity, it's the quality that counts. Visitors from those links won't be buying much either. People prefer to buy from specialists or experts, rather than a jack-of-all-trades.
Hidden Text
This technique involves filling your homepage with text that will blend in with the background colours of your website. This allows webmasters to fill their homepage with keyword rich text, while allowing their visitors to look at more appealing graphics and other features. Unfortunately webmasters who use hidden text will be identified by the search engines as spammers and penalised accordingly. We recommend you keep your website free of hidden text in order to avoid ranking penalties or removal from the search engine databases.
Doorway Pages
Another popular technique among webmasters, doorway pages are pages on your website that have been created for the sole purpose of bringing more search engine traffic to your page. People adjust their doorway pages to suit different search engines and then they're linked back to their original homepage. Sounds like a smart way to adapt your website for all of the major search engines, but of course the search engines know about this trick and will always penalise you for it. Better that you have your website optimised so that it is more search engine ready overall rather than using tricks.
Too Many Graphics
If used properly, attractive graphics and flashy multimedia can make your website look very impressive. Unfortunately search engines can only read text. So no matter how good your graphics are, your website will only acheive a good ranking if the search engines can find high quality text that contains keywords that are relevant to your site.
Frames
Search engines don't understand frames, it's as simple as that. If a website has frames, then the search engine's spider will visit the website and either leave or only look at the pages on the site that aren't in frames. Preferably you shouldn't use frames but if you absolutely have to, then make sure you have your keywords listed in your no-frames tag for all of the search engines to see.