I'm a very new player (Just downloaded the game on Sunday). I played the tutorial games and have that understanding of the game. I've talked with some friends in real life about the game and some terms that are reoccurring in the conversation are:
AD
AP
ADC
If someone can explain these concepts to me I would greatly appreciate it.
Also:
What champion would be the best for me? I have a lot of actions per minute and good control from playing StarCraft II. Any and all advice is greatly appreciated and you have many thanks in advance.

♥
-VIPER

AD = attack damage

AP= ability power(boosts damage/healing powers of MAGIC spells)

ADC = attack damage carry(this is the player who will be doing a lot of damage late game but needs help to get there)

What champion is best for you depends on what role you want to play for your team. BUT best advise would be learn 2-3 roles and 2-3 champs for the roles if you ever plan on playing ranked

ADD me in game name is ClevelandLoL if you wanna play.

Welcome to the League!

Note that some abilities scale up with increased AD (like Trundle's Chomp), some scale up with increased AP (like Tristana's Rocket Jump), some scale up with both AD and AP (like Evelynn's Hate Spike), and some scale up with another stat (like Taric's Shatter scaling with increased armor, or Volibear's Frenzy scaling with increased health).

You can tell the scaling by looking at the color of the (+??) in the tooltip. Orange means AD, light blue means AP, and other colors will be explained in the description.

If you're experienced with SC2, you won't find any champions that require very high micro skill (you only ever control one additional unit at most, and that's only with about 5 champions out of 113). You could start with a champion with a high skill cap, if you like. Maybe Jayce, Zed, or Lee Sin. It looks like none of the free champions this week are mechanically complex, but they change every week.