TLDR? Head straight to putting it all together.
time formats UTC and local time; time zones The world’s primary time standard is UTC, which is short for Coordinated Universal Time. UTC is defined as the time at the meridian with a longitude of 0°. It is the successor of GMT, Greenwich Median Time (Greenwich, UK, is located at the meridian with longitude 0°).
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XDG stands for X Desktop Group, a project to work on interoperability for free-software desktop environments for the X Window System (X11) and Wayland on Linux and other Unix-like operating systems. It eventually evolved into freedesktop.org. freedesktop.org produces specifications for interoperability, but it is not a formal standards body. Projects are not required to implement the specifications and there is no certification.
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