The X11 format is associated with the X Windows System, which is used — among others — on UNIX and Linux platforms. X11 files are bitmaps storing X Window screen caps and can come in several variations. The format is considered rare and might be difficult to open.
The quick and simple way to handle your files is to get a quality piece of software, such as reaConverter. This software is extremely efficient in managing a wide range of batch conversions. As you will soon realize, reaConverter will help you avoid spending countless hours trying to figure out how to convert multiple X11 files as once.
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