The web is full of automated tasks which do things for their owners. These are often called 'bots - short for robots. Web search engines use these, often referred to as spiders.
Search engine 'spiders' crawl around the WWW checking links and following them to see where they end up, recording key words and phrases along the way. This is good because it helps people find the Monoposto sites 'by accident'. Code embedded into websites instruct how often they should come back and check out new content.
A good search engine ranking is important. It can be done easily without costing anything. Googlebot should be given full read access to all public areas of the Mono site.
Search engines promote sites that are linked to elsewhere. If lots of sites are linking to one particular site, then google (and friends) assume that site is an authority and can be highly positioned. Thus if you have your own website, a link to
http://www.monoposto.co.uk will help boost the clubs ranking, and in return, your website in your forum signature will boost yours.
(I've just been on a course on Search Engine optimisation)
These things can be used maliciously as well....
If you had an army of bots and they signed themselves up to lots of web forums which may not have all the latest security mods done, then they can post messages. These message may often link elsewhere and its normally to boost that sites google ranking and may get a few links from forum members as well.
Whats on the website you visit? Possibly adverts for viagra. Possible sites for dodgy software, porn or even money scams. More likely there will be even nastier software which downloads automatically onto your computer - key loggers which record bank and credit card information and send it elsewhere. Viruses which remain dormant until a trigger is broadcast. What happens? Various things - your computer could be used to constantly log onto particular websites. Of little consequence if its just one computer, but hundreds or thousands could cause website servers to fall under the strain. This is called a DDOS attack - DDOS standing for distributed denial of service.
So, in summary. Search engine 'bots' good. Bad robots.....