If you've been given a link to this page, the chances are that you posted something like, "Please help me with my wireless." You might have even posted, "I have this model of laptop, please help me with my wireless."
(I use wireless as an example. This all applies to any post when knowing the hardware might be important and you haven't given us the information.)
Don't be offended by being sent here. We were all newcomers once, and we all had to learn, one way or another, how to give enough information to, as the old customer service line goes, help us to help you.
You haven't yet given us enough information to help you, so I put up this page to save myself from typing the same thing on the forums over and over again.
Giving us the model of the laptop might help, but there are so many different laptops out there, the chances are good that most of the people looking at your post won't know which wireless card it has. What is needed, when dealing with wireless, is the model of the wireless card.
The best way to get it, if you still have Windows installed on the machine, (or checked it in the shop before buying it) is to use the Windows Device Manager. Although there are Linux tools which are pretty good at determining hardware, some newer cards may be indentified incorrectly. For example, at time of writing (February, 2008) the popular Atheros AR5007EG card is indentified as an AR5006EG. Therefore, if possible, use Windows Device Manager.
In most cases, however, the card can be indentified with Linux tools. The command to use is /sbin/lspci. This will produce a lot of output, so you might want to pipe it through more.
You should see your wireless card listed. (Doing /sbin/lspci |grep -i wireless might work, but I've only tested it on my own laptop. You can try that first, as it should produce only the information that you need. If it doesn't, then use |more as stated above.)
Usually, a wireless card is in the last 4 or so lines of output. As I said, the AR5007EG is not identified properly by lspci. One thing that will help you determine if you're one of the lucky ones with it is to do lspci -nn. This will show the ID's. If you get 168c:001c as the ID number, then there's a good chance that you have that card.
As a side note, when I first wrote this, that particular card was often a cause of confusion. It now seems to be seen by most distributions as AR242x. The card was also very common, and a common problem. These days, most distributions see it and automatically use ath5k driver.
Once you have the model of your wireless card, you can put the model number in the search box of the forum you're using to ask about the card. The chances are that someone else has the same card and you might find a solution. If you do, then it's always nice to add to the thread, saying, "This worked for me too." It lets others, who might search the forums in the future, know that this card does work if one takes certain steps.
One other sometimes important point. If you post about your wireless card, it's a very good idea to put the model number in the subject of your thread. Many of us view forums while in a hurry--for example, I can often help if it's the Atheros 5007EG, someone else might be an expert on a particular Broadcom card, etc. If we're busy, and we see wireless problem, we might just skip it. However, if we see that it's about a card where we're pretty sure we know the answer, there's a better chance of us stopping to view your question. So, do your best to put the model number of the card in your subject line. This way, if the expert on your card is in a hurry and just scanning subject lines, they know that this is a person they can help.