Access to a protected system using a password can be described as going through the front door. Organizations can build "backdoors" into their systems, however, so that developers can bypass authentication and dive right into the program. Backdoors are usually secret, but may be exploited by hackers if they are revealed or discovered.
Sort for Weblog - A personal journal recorded on a website. Blogs are updated frequently and usually grouped by subject (e.g. politics, computers, religion, news, culture, et.al.). Often allowing commenting in response to the entries.
Botnets, or zombie armies, are networks of computers controlled by an attacker. Having control over hundreds or thousands of computers lets bad actors perform certain types of cyberattacks, such as a DDoS (see below). Buying thousands of computers wouldn't be economical, however, so hackers deploy malware to infect random computers that are connected to the internet. If your computer gets infected, your machine might be stealthily performing a hacker's bidding in the background without you ever noticing.
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