Cybercriminals deploy botnets for conducting nefarious operations on the Internet. Botnets are managed on a large scale and harness the power of compromised machines, which are controlled through centralized portals known as C&C panels. C&C panels are considered as attackers' primary operating environment through which bots are controlled and updated at regular intervals of time. C&C panels also store information stolen from the compromised machines as a part of the data exfiltration activity. In this empirical study, we analyzed many over 9000 C&C web URLs to better understand the deployment and the operational characteristics of HTTP-based botnets.