Luck Of The Sea?

It's good for fishing. So if you plan on going fishing anytime soon, then I would buy it.

 

It's a new enchantment added in 1.7.2 for fishing rods. I believe it increases the chance of getting a fish and decreases waiting time.

 

From the Minecraft Wiki.
Luck of the Sea: Lowers chance of "junk" catches by 2.5% per level and increases chance of "treasure" catches by 1% per level.
Lure: Decreases time before fish bite your hook by 5 seconds per level. Also decreases chances of both "junk" and "treasure" catches by 1% per level.

 

What is 'treasure' and 'junk'?

 

Find a table here depicting what is considered junk and treasure.
http://minecraft.gamepedia.com/Fishing#Usage

EDIT: This Minecraft Wiki has taught me so much about the game.

 

Thanks for clearing things up

 

You're welcome.

 

How did you get a picture like that?
~Isabella_sarro

 

@DumbDiamonds made them, ask him/her in their thread.
https://www.minetime.com/threads/making-blender-profile-pictures-open.2224/page-11#post-26581