WHAT ARE THE FEATURE/S OF SOLIDWORKS THAT MAKE AN ADVANTAGE TO CATIA.......AND WHAT IS THE EASIER TO USED ?
If you look on google images and youtube videos, the big difference is the user interface. Both have the same capabilities from what I've seen when it comes to modeling and engineering. It's all personal preference really. Best way to choose would be user interface, file type compatibility, and price. Also would be best to really look at what you will be modeling/creating.
I agree with everything Jonathan said.
I'll also add that it also depends on the company or people you'll be working with. Learning SolidWorks, or Catia is a great idea, but if the company/client wants native Inventor files (or some other file format), then the only options are talking them into something else, or using the CAD program of their choice.
Catia (in my mind) is for larger projects. A building, a plant, a vehicle (not just the "shell" of a vehicle). Catia works on those larger projects and to my knowledge allows a lot more analysis to be done on the entire product.
I've heard that Catia is a "better" option for class A curvature continuous curves/surfaces as well.
I've never used, or seen Catia. Those are just my thoughts on the differences.