Android has been heavily criticised for its OS fragmentation.
Basically each android OS has it own nickname.
Below is the list of all Android Operating System till date,
the latest is the 5.0 OS nicknamed Lollipop.
Android 2.3.3 - 2.3.7 Gingerbread,
Android 4.0.4 - 4.0.4 Ice Cream Sandwich,
Android 4.1 - 4.3 Jelly Bean,
Android 4.4.2 - 4.4.4 KitKat,
Android 5.0 LolliPop
Warning:
1. Please do backup your android system or backup
all your applications and information stored in your device
because the update will involve making all wipes.
click here to learn how to back up your ROM
2. I am not responsible neither is Android for any
consequences that this process can result for your
device if you do not follow all instruction exactly.
3. Enable the USB Debugging through Settings >> About Phone
4. Tap 7times on Build number till you see "You are now a developer"
5. If you have rooted your devices b4 skip step 4
6. Root your device here if not rooted before here
7. Charge your Android phone or device to full battery
