These are some of the basic topics that you should learn to improve your photography significantly:
- Exposure Triangle: Know the relation between Aperture, Shutter Speed and ISO.
- Composition: Learn the rules of what to include in your photographs.
- Lighting: Learn to see the light.
- Digital Potential: How to improve your photographs after you have clicked them.
- Equipment & Lenses: Which equipment to use depending on the situation.
- Photo Critique: By seeing what can improve the pictures, your future photography will become better.
By learning these topics and putting these to practice your photography will certainly improve a lot.