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.7z, .zip, .tar.xz, .rar and e.t.c - they all old, they just still get updates.
7z best for saving space (~1.5GB into ~700MB 7z archive? not a problem), tar.xz best for linux and zip is just supported by literally everything.
There other formats like .wim, .gzip and e.t.c, but they used so rarely that there not 0 chance that you never see them in your live...