Morris worm was created by a student from Cornell University named Robert Tappan Morris. It was created on November 2, 1988.
According to creator this worm was not created to damage but to find out the size of the internet. It worked by exploiting the vulnerabilities in Unix Sendmail, finger and many more. Later it was discovered that it has the power to crash the computer.
The link below shows how the Morris Worm is structured and where you can download code.
I hope it has been a useful article.