what is & how do i use cydia?

[amyleeom1213]

im new to the iphone and i have a 2g unlocked iphone i got from ebay.i luv it but want 2 update it and get all i can out of my phone.but im scared that when i update and go to unlock it i will mess it up.someone told me how to unlock again but i do not understand the whole cydia thing.how to download and where to download things like blackra1n and bootneuter.can someone plz explain

 

[Alli]

Start here: http://forum.theiphoneblog.com/ipho...e-posting-jailbreak-faq-updated-1-3-10-a.html All your questions are answered.