The PDF Edition of Ubuntu Pocket Guide and Reference is available entirely free of charge. It is practically identical to the Print Edition. You can get it by clicking one of the links below.
You can share the PDF file with people you know, and even upload it to file sharing networks. However, you may not sell the PDF!
Before downloading, ensure you read the legal
information, in particular, the disclaimer of warranty, which can
also be found on the first page of the PDF.