There are some short keys like, T for Text, L for Lesso Tool, M for Marque tool, C for Crop tool, etc., But if there is anything you want to create your own short key in photoshop, you will have to use action option.
I want to share you one of my experience that will show you the importance of actions.
Once I got a project of digital coloring. I got the artwork and had to do coloring on different layer and inking on different layer. Coloring had to do with hard brush in photoshop.
I did digital inking first with hard brush (3 pixel), then I created a new layer and locked one (inking layer). While selecting with Magic Wand Tool, I added the color on the document it was showing white space around the line. Look in the image 1:
First I selected with magic wand tool and then I use Expand option of photoshop you can see in image 2.
Image 3 is showing the entry of pixels. I used 2 pixels in this.
If you know that how to create Action then Ok, if not click here to know.
How to Create Action in Photoshop?