This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
When you connect to a web server (such as http://www.coderanch.com/) and you do not specify a particular port to use, then you must be using the default port. You can read a basic primer on HTTP in wikipedia's Hypertext Transfer Protocol article, which will tell you the default port, and it will also give you a list of relevant RFCs that will give you a much greater understanding of what is going on.