Uploading Pictures in Project with ASP .Net MVC - Session 5

ASP .Net MVC Project Development Session 5 for Trainees. In this session we learned about following Topics.
1- Difference between Dynamic and Static Page sections
2- File Upload type html input field
3- Why uploading pictures with jQuery
4- Assigning file upload change function in jQuery
5- What is formData in jQuery
6- Appending data to formData
7- Where to put common code in controllers
8- Return types of Actions in Controller
9- What is JSON? Where is it used?
10- What is JsonResult and why we need it
11- What will happen if we upload two images with same name?
12- Why replace file name with Guid?
13- Assigning value to html element attribute in jQuery
14- Applying break points to jQuery code from Source tab in inspect element window
15- Why browser not allowed to access computer local file?
16- Relationship between Business Entity and Image
17- What to do if Context change error appear in Entity Framework
18- Why we need hidden fields in View
19- What are ViewModels? Why we need them?
20- Returning ViewModels from Views
21- Checking for Null Values in LINQ