.u

File Type 1 Generic IconSubsampled Raw YUV Image
File Format Standard
Usage Open manually
Rank ★ ☆ ☆  Uncommon
Description

One of three files from a split .PPM file; others are .V and .Y files; YUV representation is used by the Stanford MPEG codec.
Open With
Windows

IconMicrosoft Windows Media Player with YUV ...

IconApple QuickTime Player with QuickTime YUV codec
macOS

IconApple QuickTime Player with QuickTime YUV codec
Unix

Iconppmtoyuvsplit

Iconyuvsplittoppm
Updated 2007
File Type 2 Generic IconAU Audio File
File Format Standard
Usage Open manually
Rank ★ ★ ☆  Average
Description

Audio container format typically used to store ?-law encoded audio data; introduced by Sun Microsystems and also used by MusicKit for the NeXT operating system; contains a header that includes six 32-bit words, an optional information section, then the audio data.

AU files typically use the .AU extension.
Open With
Windows

IconApple QuickTime Player

IconMicrosoft Windows Media Player

IconRealNetworks RealPlayer Cloud
macOS

IconApple QuickTime Player

IconRealNetworks RealPlayer Cloud
Updated 2007
File Type 3 Generic IconUnreal Tournament Class Package
File Format Proprietary (Epic Games)
Usage Open manually; may be referenced by an application
Rank ★ ★ ☆  Average
Description

Contains settings used by Unreal Tournament; stored within the Unreal System directory, i.e. "\Unreal\System\Engine.u;" may be replaced with custom class packages.
Open With
Windows

IconEpic Games Unreal Tournament

IconEpic Games UnrealEd

IconDragon UnPACKer
macOS

IconEpic Games Unreal Tournament
Updated 2007
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