Can you explain me the deference between these comments /** */ and these /* */ ?

Question

about comments

Answer 1

Java comments starting with /** ( two stars used) can be processed to create javadoc documentations.

Answer 2

There is no difference between any comments. No matter they way you make it.
The only thing that you may consider, is following the IDE or text editor you use, you can specify more details about methods.

Example on sublimText :
/**
* @author
* @version
* @param
* @return
*/

If you do not start by "/**" you will not have any visual distinction.

Another example for Visual Studio. It's quite the same thing, but the structure of the comment is automaticly created if you type "///" before the method.