Recently, I rooted my Samsung Galaxy S5 as I needed some additional futures of my smartphone and I had to install some android apps which require root access. 
What does it mean rooting phone devices? It means, doing special procedure and flushing some part of the memory to be able to get access to all your data on your phone as a superuser (SU) – admin. Don’t worry, you don’t lose your data (photos/mp3/etc.). Having that you can install some special third-party applications which require admin access but also you have to be aware that you lose your warranty by rooting your device. I am not sure if you can restore your warranty status by reinstalling the latest official firmware from Samsung. Be aware of that and decide if you want to root your phone. 
Necessary requirements:
- Turn on debugging mode on your device. On Samsung Galaxy S5 (or any android device with system version 4.2 or newer). You can do that by going to “Settings”->”About phone”. Then tap “Build number” 7 times quite rapid. You will notice some counter with the number of taps left. Next go back and find “Developer options”, go there. Turn on “USB Debugging”
- Install all necessary USB Drivers for Galaxy S5 on your computer. You can do that before starting rooting. You can also allow windows to automatically install all necessary devices from the internet when you connect your phone during rooting.
- Just in case, you can backup your data to avoid potential lose during root setting.
- Check if you phone has at least 60-80% battery charge
- Check your model number in “Settings”->”About Phone” and download appropriate package on your computer from the list below
Download appropriate CF-Auto-Root tool for your device:
- SM-G900F — International Snapdragon (Download)
- SM-G900H – International Exynos (Download)
- SM-G900I – Oceania (Download)
- SM-G900L – Korean model (Download)
- SM-G900M – Model for Middle East and South America (Download)
- SM-G900RT – US Cellular (Download)
- SM-G900T – T-Mobile United States (Download)
- SM-G900P – Sprint (Download)
- SM-G900T1 – MetroPCS (Download)
- SM-G900W8 – Canadian model (Download)
Download Odin app:
You should use Odin application (Samsung Flashing tool) to root your Galaxy S5 (but not only, it is universal). You can find this app in each archive zip file from above links.
Rooting process:
- Unzip the proper downloaded package.
- Run Odin app as the administrator (you might click on “run as administrator”).
- In Odin app, select the PDA button, then select the .tar.md5 file. You can find that in your CF-Auto-Root extracted folder.
- Turn off your Samsung Galaxy S5.
- Press the power, home and volume down buttons together. Wait for the screen to boot. You will see the special screen and then press volume up to proceed.
- Connect USB cable to your phone. All drivers should be installed automatically on your windows. If not, you can do that manually.
- After proper connecting an USB cable with you device you should be able to see some message in the “Message” console/window/text field and light blue field in the ID:COM bar.
- Make sure that “Auto Reboot” and “F. Reset Time” options are checked while “Re-partition” is unchecked
- Press “Start” button and observe the console and your phone screen. There should be some information messages and your phone should reboot after all.
Checking Root Access
Install “Root checker” application from google play and open it. You should grant “super user” permission to this application and check the message. There should be some text which tells you if you device is already rooted.
