Adobe Photoshop is unfathomably complex with so much nuance, it would be difficult for any person to ever say they have mastered the software. In this brief video, you'll learn how eight of the blending modes are different from the rest and in the same way, and just how powerful they can be.
Ordinarily, I wouldn't write about content that is as brief as this video, but I'm going to make an exception on this occasion as it's more informative than most videos ten times longer.
The Photoshop Training Channel goes through eight blending modes in this video. They are, Color Burn, Linear Burn, Color Dodge, Linear Dodge (Add), Vivid Light, Linear Light, Hard Mix, and Difference. These blending modes work in a way in which the layer's Opacity and Fill do not create the same outcome, whereas with the remaining blending modes, they do.
This may seem an innocuous tidbit of information, but it's profound in the right hands. Blending modes give a lot of creative control in post-production and when you are editing your images, subtlety is often the key. With both opacity and fill working with the aforementioned blending modes, you have more flexibility and can create more realistic and pleasing results.
This is one video I would bookmark if you are learning Adobe Photoshop, it's concise and highly useful.