There are many ways to mess up your computer, so read on and learn some of the basic problems that people cause themselves by not being careful!
Your friend sends you this joke and you want to read it because everyone loves to laugh. You click on the link and suddenly your computer has slowed down and you have no idea why. That joke may have contained "Malware" which is written into the email to put backdoors etc on your computer. So you get upset and call your friend and find out that they did not send that to you. That is how a Virus/Malware work. While you are staring at the screen, the virus is taking your address book and sending this same "Joke" to everyone on your email list. But don't worry, your address won't show up, it will select one name for the "To" line and another for the "From" line so your friends will wonder where it came from just like you did. Now I am not saying that you should not read jokes, just stay away from the links.
Your friend sends you this joke and you want to read it because everyone loves to laugh. You click on the link and suddenly your computer has slowed down and you have no idea why. That joke may have contained "Malware" which is written into the email to put backdoors etc on your computer. So you get upset and call your friend and find out that they did not send that to you. That is how a Virus/Malware work. While you are staring at the screen, the virus is taking your address book and sending this same "Joke" to everyone on your email list. But don't worry, your address won't show up, it will select one name for the "To" line and another for the "From" line so your friends will wonder where it came from just like you did. Now I am not saying that you should not read jokes, just stay away from the links.