Gary C. Kessler's "An Overview of Cryptography: Some of the Finer Details of RSA Public-Key Cryptography"
Read section 5.3 about the steps in the RSA Public-Key Algorithm. After reading, you should be able to describe a simple example of generating public/private keys for RSA systems and describe the process of encrypting and decrypting a message.
Click http://web.archive.org/web/20160702191723/http://www.garykessler.net/library/crypto.html link to open resource.