Do you change the oil and spark plugs in your car? Does your computer seem to run slower than when you bought it? Lock up often? Do you perform maintenance on your PC? If not, just like with your car, your computer will get slower, less responsive, not start or run right, and cause a lot of problems.
Think of your computer as a toy chest. You play with something and when you are done with it you toss it back in the box. Every time you do this, your "toys" get more mixed up. Eventually, if Mom and Dad don't re-sort your toys, games, and puzzles, you can't find all the parts of anything to play.

Visualize your RAM (Random Access Memory) as a hand reaching into your hard drive to pull out a program to run. If that "hand" has to look all over your hard drive for the parts to the program, it can use up all its energy just opening the program, let alone running it.
Run Maintenance on your PC (scandisk, defragment, & get rid of Temp files). Get the speed back!

Quick Ask Zoe
What Stops X-rays
Even Dogs Can't
Red Fish Vanish
Then Grow Bigger
Yaks Hear Noises
Under Jack's Mattress
I Keep commas's
Over Long periods's
Peanuts

Look for the smaller pay per click search engine, where you can get good placement for your keywords for 1 or 2 cents.

Many of the top search engines now rank sites by "link popularity". This is determined by how many sites link to yours and how those sites are ranked.
You can move up the rankings simply by trading links with high traffic sites.
Of course the high traffic sites want to trade only with high traffic sites, so for the rest of us: sign their guestbook (usually allows a URL), join a link exchange, etc. It works!