The EOT (Embedded OpenType) file format is a compact form of OpenType fonts designed by Microsoft for use as embedded fonts on web pages. It allows web developers to include custom fonts on their websites, ensuring that visitors see the intended typography even if they don't have the font installed locally. EOT fonts are typically compressed to reduce file size and improve loading times. They also incorporate licensing information, which can restrict how the font is used. This helps protect the font designer's intellectual property. EOT fonts were primarily used by Internet Explorer, but modern browsers have largely moved to more open and widely supported formats like WOFF and WOFF2. While EOT is still supported by some older browsers, it is generally recommended to use WOFF/WOFF2 for better compatibility and performance. The format includes features for font subsetting, which allows only the characters needed for a specific webpage to be included in the font file, further reducing its size. EOT files are often served with specific HTTP headers to ensure they are correctly interpreted by the browser.