using keyword can use two places 1.) when adding a namespace 2.) dispose the object automatically when the class implement idisposable interface.

“Using” statement calls – “dispose” method internally, whenever any exception occurred in any method call and in “Using” statement objects are read only and cannot be reassignable or modifiable.

Developer the desktop application

The reason for the using statement is to ensure that the object is disposed as soon as it goes out of scope, and it doesn't require explicit code to ensure that this happens.

for implementing IDisposabel interface