Start With Xcode on Intel Based / Power Pc Based Macintosh

Lets take start with Xcode, Xcode is an environment in which you code for iphone applications ,
First of all you need an intel based Computer with almost 3.0 Ghz processor and 2GB of ram, 80 GB hard drive is enought. you can run apple macintosh on you intel machine by installing IATKOS v5.5 or later , search for IATKOS on google you will find free downloadable link of intell based mac, you can install this easily on your intel pc, or if you have macintosh so its good.
Install Xcode by apple official web site if you have intel based mac , other wise you have to search on google for Iphone SDK 2.2.1 , its an old version , for powerbook g4 , install official sdk 3.0 if you have macbook.

How to develop iphone applications

First of all we need to go to apple's web site to study some basic concepts . you can easily switch to iphone , (objective c) if you have any idea about framework programming languages. i will upload some sample projects and tutorials very soon