
The above is just some of the information given out by your browser, which can be logged. If there is no information above, you're using a Privacy Browser which hides this.
It isn't logged by me, but most server companies do and they usually provide a program to analyse the data. I can see what percentage visitors come from a certain country, pages viewed and which search engine they used to get here, even the search word used, if any.
Your IP address can also be traced for more details by going to one of the sites below, to find out your company's name. Some sites record all the information and pass it on to worldwide databases for market research.
The four organisations covering the world

You can trace anyone's IP details by using the appropriate sites
Cookies are set on nearly every website, but I have stopped using them. If you look in your cookies folder, you'll probably find a full page of them. You can disable cookies if you wish, but some sites won't let you enter if you have them disabled. Some cookies save your login information to a site and welcome you on a return visit. If you like this, don't delete all your cookies.
Cookies are usually stored in 'C:\WINDOWS\Cookies' (for Windows 98) or in 'C:\Documents and Settings\Your User Name\Cookies' (for Windows XP). These are simple text files and you can read them with "Notepad" or any text editor.
A cookie can NOT pass a virus to your computer as some people think. You can delete all your cookies by right-clicking Internet Explorer, select Properties, then click Delete Cookies. I do this regularly, as some sites have got together and monitor where your cookie goes. The information is used to see which sites you visit, but not really that dangerous.
Spyware is something very different. It is usually built into a program that you have downloaded for free, such as certain music download programs, but not all do this. This type of program can (when you access the net, or if you're on broadband, at any time) transmit information to them without your knowledge. The information might include what music you play on your computer, even though you didn't download it. This seems quite scary. If the program is on your computer, what else is it capable of?
It's usually in the (very very) small print that you agreed to let them use certain information if you install and use their software, so it's not illegal.
You can download a free version of Ad-Aware SE Personal which seems to be the most popular spyware detector and remover. I've used this great program. It takes quite a while to scan, but then look how many individual files there are to check. It searches every file on your hard-drive, then gives you the option of removing the offending code. Sometimes after the spyware code is removed, the program no longer works.
The first time I used Ad-aware, it found 2 programs that I'd been using. Both programs refused to work following being cleaned so I totally uninstalled them on principle. If you get Ad-aware, I'd suggest running it at a minimum of once per week, and you must update it regularly. It sometimes finds cookies that it classes as spyware. These are not true spyware as they can't transmit data, but can track you from site to site. They are of no use to you, so delete them.
Spybot Search & Destroy is also very good (plus it's free) and finds stuff that Ad-aware doesn't. You really need both to get rid of spyware. When I first started using it, it found 53 'BackWeb lite' entries. These can be used legitimately for automatic updates, but can also be misused.
Be careful where you download any free programs from, as there are some bogus sites out there posing as the original sites, and are actually installing spyware when you download their freebies.