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PDF Files (Adobe Acrobat)
This is the most common format for ebooks.
Many ebooks appear in CHM format.
To find out more about how to read a CHM file, click here.
DOC Files (MS Word)
Microsoft Word Files
Sometimes you can find books in this format.
RTF Files (Rich Text)
Sometimes you might find books in this format.
TXT Files (Plain Text)
When all else fails... try this.