I have a Samsung Galaxy Stellar on Verizon.
Whenever I hear anything about rooting a phone, people always say that you have to install a custom ROM. How do I just use my current stock ROM and root my phone?
In theory - yes.
In practice, it varies from device to device - a very common way of an end-user obtaining root is to flash an insecure kernel. This can be a standalone kernel or a pre-rooted kernel + ROM combination. For certain devices, there are also available a number of 3rd party "one-click rooting" apps.
That being said, rooting might cause your device to be unusable (if not done correctly or something unexpected occurs), so read the instructions carefully before proceeding and ALWAYS backup your data to an external source like Dropbox or to your PC before you begin.
Here's a link (unverified) on how to root your Verizon Stellar.
That very much depends on your device, as the rooting process often is device specific. Following up to the rooting tag wiki will give you some basic info, and also provide a link to our rooting index, which might even already include a link for your device.
Basically, rooting just means to push a binary (
su) and a helper app (SuperUser/SuperUser or SuperSU) to the system partition. So as Compro01 wrote in his comment on your question, you're "customizing your ROM" somehow.
On most devices that's all you need, though how that's accomplished is a different thing, as it's a little chicken-and-egg: You want to gain root permissions on your device – and for that, you first have to push those two files to
/system, which only can be done with root permissions. So in most cases, this requires some "hacking", which is what Sparx refers to in his answer might cause your device to be unusable. I rooted several devices already, and when sticking to the instructions the device should not become "unusable" (though I admit there might be rare cases). I had it once a device became instable (apps crashing, device rebooting itself multiple times a day), but that was easily cured by a factory reset.
The answer is YES .
It is not mandatory for you to install custom ROM for rooting your device. ROOTING process is a actually YOU ARE GETTING ALL THE PRIVILEGES of your phone . So it is not necessary to install Custom ROM
Steps to Do Rooting :
I can help you in your rooting process if you tell me which device you are using.
here is an Unverified way to do it (Samsung Steller).
Kingoroot - you can download it to your phone and root with one touch or onto Windows and root via usb, it requires no flashing so is safe and takes up to two minutes. I used it on my Samsung Galaxy phone and it worked fine (may need to do a couple of tries). It even installs super user (a root access manager) app for you.
Mainstream phones are easier to root since their source is well adopted. Less familiar phones can be harder to root. Why? When you're rooting, you're adding one functionality to the phone which is initialized at boot; that is to run the
SuperSU Daemon which utilizes the
su binary in coordination with the Kernel to work in providing elevated permissions over Read Only File Systems like the
/system. How is this achieved? The Kernel has to be patched to be able to do this since that's another third party services being added. If a phone has an unpatchable
boot.img. All these things might require installing a third party
boot.img which still support the current system to be able to root. Failure to find a way to develop a
boot.img that will support the system will require you to install a full Custom ROM to be able to do this. Remember the
kernel is in the
boot.img together with something they call the
ramdisk that's why you should talk about
boot.img if you're taking about Kernel in Android. It is either possible to root without Custom ROM or Impossible depending on your device