I've been using Photoshop since 2011, much like everyone, I used to think Photoshop was the software for ALL design, however since trying different software, I've learnt that Photoshop is only for Photo Manipulation of raster Images.
I've recently started using the new Experience Design Beta from Adobe, it's there to simplify design for clients, and I think it's fantastic, it saves me from looking through layers to find what I need. I'm still learning the keyboard shortcuts.
Not many people realize that if you design a Logo that's pixel based (Photoshop), if you ever want to scale it, it'll never work as it'll be pixelated, Illustrator overlooks this by using Vector Graphics, and can be scaled as the client needs.
Casading Sheet Styles
CSS was a confusing language for me to start, I was unaware on how it worked, however I slowly learnt how the languages communicate with CSS and how it works, I'm still a bit stiff in some areas, and I'm always trying to touch up my skills with CSS.
Hyper Text Markup Language 5
HTML5 is a simply more advanced version of HTML, however I have a great understanding oh HTML and how the elements work and fit together, I still think there's room for improvement and I'm always willing to learn new Tips and Tricks.
I understand basic PHP such as IF statements, however I'm still learning the more advanced areas of PHP. I can understand PHP if I'm backwards reading it, however sometimes writing it can be an issue for me.