How to Solve a Rubik's Cube-2nd layer

Here is part 2 of my 4 part solution to the Rubik's Cube. This part will focus on the 2nd layer so you should already know how to solve the first layer or have it solved beforehand.

Difficulty: Moderately Easy

Instructions

Things You'll Need:

• Important symbols to know:
• F(Front face)
• L(Left)
• R(Right)
• U(Upper)
• D(Down)
• B(Back)
• R(no ')= rotate side one quarter turn (90°) CLOCKWISE-in this case, rotate right side
• U'= rotate side one quarter turn (90°) COUNTERCLOCKWISE-in this case, rotate upper side
• D"= rotate side one half turn (180°)-in this case, rotate down side
• IMPORTANT NOTICE: rotating clockwise and counterclockwise is with respect to that specific side (pretend looking at the side as if it were a clock and rotate accordingly

1. 
   U' F' U F U R U' R'

   The 2nd layer is actually pretty simple after you solved the first layer since you really only have to put in 4 side pieces to complete the layer. So here's 3 different scenarios for you to follow. Again, put the cube in the same positions as shown and perform the corresponding algorithms. Here's the first scenario pic

2. 
   U R U' R' U' F' U F

   2nd scenario pic

3. 
   R U R' U' F' U' F U' R U' R' U' F' U F

   3rd scenario pic

4. 
   2 layers complete

   And there you go, the 2nd layer is complete.
   
   Here's what it'll look like (of course)
   
   Now for the 3rd and hardest layer.