Nessus Essentials is a free vulnerability scanning tool from Tenable, Inc., designed for students, educators, and small-scale users to perform high-speed, in-depth vulnerability assessments on up to 16 IP addresses per scanner. Part of the renowned Nessus family, it leverages Tenable’s extensive plugin database (over 252,000 plugins) to identify security weaknesses, software flaws, and misconfigurations across networks, devices, and applications. Introduced as a rebranded Nessus Home in 2019, it’s ideal for personal home networks, educational purposes, or small businesses starting in cybersecurity. Nessus Essentials runs on Windows, Linux, macOS, and platforms like Raspberry Pi, offering a web-based interface and NASL scripting for custom plugins.