I'm someone who needs to understand the basic process and terms of an endeavor before I will proceed. While there may be specific instruction sets for each application you might use to jailbreak, I wanted to document the overall process so that you can mentally match up what you are doing in the software with where you are in the process. Since I had some difficulty understanding the steps and terminology involved with jailbreaking, I thought I would make a quick list of what is involved in jailbreaking, both for the benefit of others and for you to review and make sure my understanding is correct:

Jailbreaking

Not one step, but a combination of these basic steps that proceed generally in this order (the order is presented in a logical fashion, but depending on the 3rd Party Application, some steps may change order):

STEP 1. Pwning with a 3rd Party Application
STEP 2. Downloading original Apple Firmware via a 3rd Party Website such as modmyi.com
STEP 3. Using the original Apple Firmware to create custom firmware with a 3rd Party Application
STEP 4. Using the iTunes restore functionality to install the custom firmware to your Pwned device.

Once you have reached the point where your custom firmware is installed and running on your device and you can use it normally, your device can now be said to be Jailbroken. Jailbreaking DOES NOT include unlocking. Unlocking your phone is a separate separate step that comes AFTER and REQUIRES you to jailbreak your phone. Jailbroken may also refer to the custom firmware that will be download to your device.

STEP 1: To Pwn or Pwning your iPhone/Pod

The process that allows your iDevice to accept custom firmware not provided by Apple. A device only needs to be Pwned ONCE and it will then accept custom firmware FOREVER. However, if you ever update your device using original Apple firmware, it will UN-Pwn your device and you will have to Pwn is again before it will accept custom firmware again.

Make sure the 3rd party application you download supports the type of device and version of firmware you have. Programs that will Pwn your device and prepare it for jailbroken firmware

PC:

1.
2.
3.

Mac:

1. pwnage tool
2.
3.

iPhone/Pod Firmware

A combination of the operating system (like Windows on a PC) and the software that runs on the device. You can see your current firmware version in Settings -> General -> About -> Version. Jailbreaking usually only refers to this firmware. When a specific firmware version has been jailbroken, you may also hear that said version has been hacked or cracked.

Baseband

The microchip that handles communications on the iPhone. Most importantly to users here is probably that the baseband is what talks to your Carrier or Service Provider (AT&T, Verizon, T-mobile, Sprint, etc.)

Baseband Firmware

The software that controls the Baseband chip. You can see your current Baseband firmware version (which will be completely different from your device firmware) in Settings -> General -> About -> Modem Firmware. Unlocking usually only refers to this firmware. When a specific firmware version has been unlocked, you may also hear that said version has been hacked or cracked.


The difference between original Apple firmware and custom firmware
:
===================
Original Apple Firmware: Apple provides regular updates to their iPhone with new features (recently, the addition of Cut and Paste was a big deal made possible by new firmware) and bug fixes (recently, they fixed a problem where phones would not wake from sleep mode). Apple firmware packages (with *.ipsw extensions) can contain either firmware updates only OR firmware updates AND baseband firmware updates. For people who want to unlock their phones, this is bad, because phones are unlocked only for a specific baseband firmware version. Therefore, once unlocked, you don't want Apple updating your baseband firmware without you knowing. You can update your baseband firmware manually on your own once you know it has been cracked and is unlockable.

Custom Firmware: can have the original device firmware separate from the baseband firmware and update only one or both depending on want you want. Whereas original Apple firmware only comes with the basic apps like Google Maps, Notes, Stocks, Weather, Safari, etc., custom firmware can come prepackaged with additional apps that will aid you in customizing your newly Jailbroken device. Custom firmware also allows the installation of additional custom applications beyond those approved by Apple. Finally, and most importantly for those wanting to unlock the custom firmware can be pre-activated for use with Carriers or Service providers other than AT&T.
===================

Cydia

A custom application that functions like Apple's App Store but allows you to easily download and install OTHER custom applications to help you customize your jailbroken iPhone. Almost all custom firmwares come with Cydia prepackaged because it is the most popular, easiest to use, and mature gateway to your continued customization of your device. You can find, download (and even buy) and wide variety of apps here that only work on jailbroken phones. Many apps that get rejected by the Apple store end up in the Cydia store. There are alternatives to Cydia such as Icy (which I know nearly nothing about) and predecessors such as ********** (which I know nearly nothing about). You can technically have a jailbroken device without having the Cydia app installed, but it would be nearly useless as it would be very difficult to do anything you couldn't do before you jailbroke without Cydia.

STEP 2: Downloading original Apple firmware

These are *.ipsw files that contain your firmware and standard apps. The firmware version that is currently on your iPhone DOES NOT necessarily matter. When you update your firmware via iTunes, they are simply replacing the old firmware (software) with the new firmware (software). So if you download a newer version of firmware than what you currently have, and use that to create your custom firmware, then you are simply doing the jailbreaking process and the normal update process in one step! Generally, this is a good thing so long as the newest firmware is jailbroken and there are no major bugs or feature problems with the newest firmware. If you are trying to download and create a custom firmware from an OLDER original firmware than what you currently have, then this would fall under downgrading and is not something I know much about and may have specific steps for each version.

There are at least three places I could recommend you get a copy of the original Apple firmware:

1. From iTunes itself. With your device plugged in and iTunes on, if a newer version of firmware is available, a Download button will appear in iTunes. Clicking this button will give you the option of downloading the file WITHOUT updating your device. You can then choose to save it wherever you want and use this file to create your custom firmware. This only works IF there is a newer version of firmware available and IF you want to work with the newest version.

2. Apple Forums & iPhone Forums, Mods, Hacks, News, Themes, Downloads, and more! | ModMyi.com - Downloads - Firmware You must be a registered user to download from here. Make sure you match both the device type AND the firmware version you want to work with.

3. iPod and iPhone Firmware Download I've seen several people link here: no registration required.

STEP 3: Creating custom firmware using original firmware

Can be done with several 3rd Party applications. This is where you take your original Apple firmware and perform some combination of:

1. Choose to pre-activate for non-AT&T carriers
2. Choose to not install the baseband firmware update
3. Choose to install Cydia or an alternative
4. Choose a custom boot screen
5. Choose any additional apps you want pre-packaged

Everything else needed to produce a custom jailbroken firmware will be done automatically by the application. Make sure the software version you get supports the device type and firmware version you want to use:

PC:

1.
2.
3.

Mac:

1. pwnagetool

STEP 4: Using iTunes Restore to install custom firmware to your device

1. Plug the device in
2. Open iTunes
3. After it is detected by iTunes, you will see a Restore button in iTunes (if your device is in recovery mode, you will ONLY have a Restore button)
4. Click the Restore button while holding down the Alt Option key (on the Mac) or the Alt key (on a PC)
5. A window will open allowing you to browse to and select your newly created custom firmware. Select it and click Open. (If you do not see a window allowing you to browse to the custom file, then you did not hold down the right key while clicking Restore!)
6. Your custom firmware will begin to transfer to the device.

Activation:

Your device must be activated to work with Carriers or Service Providers such as AT&T, Verizon, Sprint, T-mobile, etc. Since AT&T is the only official carrier that you can use an iPhone with in the USA, it can be activated through iTunes after jailbreaking without any special steps (it is done automatically after the custom firmware installation process and your iPhone will notify you of activation status). To activate an iPhone that will receive service using a different carrier, the custom firmware must be modified to spoof the Apple activation servers and fool the iPhone into thinking it has successfully activated. This generally happens during the custom firmware creation process, and is usually as simple as selecting the right option. Software that supports activation for use with a carrier other than AT&T:

PC:

1.
2.
3.

Mac:

1. pwnagetool
2.
3.

Unlocking:

This is the part I understand the least, because I use AT&T, and so have yet to unlock my phone and, more importantly, have yet to test to see if or how it works. But I will be using it when I travel internationally.

Even if your phone has been Activated and can be used with other carriers, it won't be able to actually communicate with them until the baseband firmware is unlocked. A locked phone means it will only communicate with the one carrier defined in the baseband and the sim card from that carrier. An unlocked phone can accept any sim card from any carrier and receive service (though you should note that advanced features like MMS and data may or may not work right on other carriers).

Unlocking is usually done via a simple app that you can likely download from Cydia, such as:

1. Ultrasn0w
2.
3.

The End

I welcome any comments, criticisms, or additions!