Below is a video on how to use all of the icons on the Developer. If you scroll down below the video, you can get clickable quick access to each of the icon explanations in the video shown below.

0:00 Developer Ribbon Icons

0:37 Macros Icon

3:04 Add-Ins Icon

3:48 Insert Controls

4:46 Properties Icon

4:56 View Code Icon

5:15 Run Dialog Icon

5:22 Source XML Icons

6:20 Visual Basic Icons

7:45 Object Browser Icon

8:33 Duplicate

8:42 Insert Breakpoints

9:15 Immediate Window

9:49 Watch Window