EOT (Embedded OpenType) is a legacy font format designed by Microsoft for use as embedded fonts on web pages, primarily for Internet Explorer. It is a compact form of OpenType that includes digital rights management (DRM) features to prevent unauthorized extraction. While largely superseded by WOFF and WOFF2, EOT is still relevant for supporting older versions of Internet Explorer (IE8 and below). Sample EOT files are used to test backward compatibility for legacy web applications. Developers use them to ensure that websites still render custom typography correctly on older Microsoft browsers. They are also used to test font conversion tools that generate EOT files from standard TTF or OTF sources for comprehensive cross-browser support.