Gary C. Kessler's "An Overview of Cryptography: Public-Key Cryptography"
Read section 3.2 about the key concepts behind public-key cryptography. After reading this section, explain the history of public-key cryptography, the factorization problem, and describe how RSA works.
Click https://web.archive.org/web/20160702191723/http://www.garykessler.net/library/crypto.html#pkc link to open resource.