Which Linux OS is better to learn Linux Administration

Hi,
I am newbie, just entered into the Linux network. I have noticed too many flavors in google and I am really confused to choose a standard flavor to learn System Administration. Please recommend a Linux Distribution to start my career.
I am newbie, just entered into the Linux network. I have noticed too many flavors in google and I am really confused to choose a standard flavor to learn System Administration. Please recommend a Linux Distribution to start my career.