How to root your Android phone

So rooting your phone gives you lot of freedom and brings out your phones abilities to the maximum.
There are many guides available to root your phone. I am just gonna mention that here.
Note: This method is for rooting Android 2.1 phones. It doesn't workout for 2.2 and higher versions(Which i am not sure of) If this process shows up a failure then try the method mentioned at the bottom of the post for rooting.

But before you get started, don’t forget to enable USB debugging on your phone by going to Settings->Applications->Development and enabling “USB Debugging“

Also you need Android SDK kit and also latest Java version installed in your PC. You can download Java from Java's official website. Also you need to have the necessary drivers of your mobile brand upto date.
I am referring to Kies for Samsung. Sony Ericsson PC companion for SE phones. Without all the above this process wont work out.

Now we are set up to start things. Download Super One Click. Extract the zip.
Click the Super One Click icon to run it. When Super One Click launches, you’ll see several large buttons at the top of the screen. Make sure your phone is connected to the computer via USB and that the debugger can “see” it (activity will start logging). Make sure your SD card is not mounted, and go ahead and click “Root” in Super One Click.

You’ll see the scrolling activity as SuperOneClick does it’s job, with “OK”appearing after each task. You may see warnings, but so long as it doesn’t “hang” on waiting for device, things should keep scrolling until it finally returns the “Success!”message.

 

At this point, check out the installed apps on your phone and you should see a “Superuser” icon that looks like a Droid skull and crossbones. If you see it, you’re rooted. If you don't , I’d suggest rebooting even if you do see it, as I had some issues getting rooted apps to work until I actually rebooted my own device. 

When you open up Supe rUser, you’ll see that you can configure notifications so that no app can actually run with root access unless you give it permission.

Whenever you run an app that requires root (superuser), you’ll see a notification requesting permission. I like this because it also means that if an app gets installed and tries to utilize superuser access without your knowledge, it can’t.

If you check off “Remember”, the program gets added to the list of “approved”apps with superuser access. You can see the ones on your list when you click on the “Apps” tab.

As you can see, once you have SDK installed and connected to your phone, the process is as simple as installing and running Super One Click. The program takes care of rooting your phone from the PC. Finally, you can enjoy a rooted Android phone, and all of the fun and excitement that offers!

You can also unroot the phone using the unroot button over there in Super One Click. The General fact is that your phone loses its warranty once its rooted. So to recover it you can pretty much unroot it for claiming it. So don't worry. :)

Well the above method isn't successful for Android 2.2 and higher. I am not sure of it though but here is the widely followed method for rooting 2.2 and higher phones.

For rooting Android 2.2 and higher:
Download this zip file for rooting. Root
Copy it to your memory card.
Then enter into recovery mode.
There are different methods for entering into recovery on different mobile phones. So search for your method in the internet.
Now in the recovery mode Select " Install custom zip from SD card or similar option to it and then install the zip and reboot the phone. You would have your phone rooted.
To unroot download this zip file Unroot and follow the same steps.