Throw; or throw E

If an exception is caught, how does one throw it again.
Catch (exception e) {Throw;} or catch (exception e) {Throw E ;}

Throw; the original exception stack information is retained. This facilitates debugging and easily finds the wrong line number.
Throw e will retain the exception information, but it will modify the exception stack information. The row throw e will become an error row, instead of the one you call in try.CodeThe actual error line.
So. Throw should be used to throw an exception again ;.
When will throw E be used?
It seems that you only need to throw a new exception.
Who can make it clear?