.LETTER File Type - Undeliverable Mail File
In Windows .LETTER File Open With
- Sendmail
In Mac .LETTER File Open With
- Sendmail
In Linux .LETTER File Open With
- Sendmail
Operating System (OS)
An operating system is the software that directly manages a system’s hardware and resources, like CPU, memory, and storage.
Mac
macOS is Apple's operating system for Macintosh computers. It offers a user-friendly interface, integration with Apple's ecosystem, and features like iCloud and Siri. It provides a stable and secure platform, empowering users with a range of built-in apps and a seamless experience across devices.
Windows
Windows also known as Microsoft Windows or Win is a graphical operating system developed and published by Microsoft. It provides a way to store files, run the software, connect to the Internet, and lots more.
Linux
Linux is an open-source, community-driven operating system (OS) that is built on the Unix foundation. It offers compatibility across various computer platforms, such as x86, ARM, and SPARC, and extends its support to computers, servers, mainframes, mobile devices, and embedded systems. With its widespread adoption, Linux has become one of the most extensively supported operating systems available.