My mobile phone is locked! What are PIN and PUK codes?

When you purchase a SIM card you get a receipt on witch, depending on what company it is bought from, you will get a set of either one or two, 4 digit PIN and 13 digit PUK codes. If you put in wrong PIN code three times in a row then the SIM card will be locked "temporarily" and you will need to put in a PUK code to change the PIN code and unlock the SIM. If you enter the PUK code wrongly 10 times in a row your SIM card will be locked "Permanently" and has to be exchanged, In other words "Be more careful with PUK code!". Some companies do keep track of these codes some don't, If you have lost that piece of paper with codes on, you should contact your service/phone provider, if it is monthly paid contract you will most likely be able to get the PUK code from them if they don't have the code or your SIM card is " Prepaid" then they may charge you about 10-20 bucks to send you a new SIM card and a new set of codes.
Best regards SciPhinx