For this chapter, we'll be looking closely at network communication. To that end, I'll be using the Wireshark packet sniffing tool to demonstrate some of the concepts we discuss. If you want to follow along and explore the network traffic on your own machine, Wireshark is a free download, available at https://www.wireshark.org/.
Whether you plan to use it to follow along with this chapter or not, I absolutely recommend familiarizing yourself with it as a tool. If you are at all serious about doing any meaningful network programming with C#, low-level traffic inspection will be a major key to your success and the earlier you learn the tool, the better off you'll be.