Do not use third-party "mirror" sites (like Softpedia, FileHippo, etc.) if you can avoid it. While many are legitimate, the risk of downloading a tampered file is never zero. Always go to the official eset.com domain.
Government agencies, financial trading floors, and industrial control systems often operate on networks physically disconnected from the internet. The offline installer is the only way to keep those systems protected with updated definitions (via a periodic offline update package).
ESET Smart Security is a comprehensive security solution developed by ESET, a renowned cybersecurity company. This software offers a range of features to protect your devices from various types of threats, including: