What is the difference between Linux Commands "useradd" and "adduser"?

What you prefer to use between useradd and adduser and why? What is the basic difference and difference in the approach of both command? why there exist two command for the same task? Which of the two is most widely used and why?

Please take a little time to answer this if you know.

In Redhat Linux “adduser” is a soft link to “useradd”.

They do the same job.
“useradd” is a native binary, while “adduser” is a perl script based on this binary.
“adduser” is more user-friendly-it is easier to work with it.