The watermark, also called the soft DRM, because it is a non-invasive form of eBook protection.
How it works: the book contains the name and / or email of people who bought the book, so that, in case a copy is pirated, you can find out who has made it available online for free. You can create your own watermark our use the default StreetLib one.
An eBook protected by the Watermark can be read on all e-readers, tablets, smartphones, and computers.
The watermark does not impede reading for those who legitimately buy the book, as opposed to the obstacle created by DRM protection, which is difficult for those who actually buy the book, and often discourages the purchase of the same. Here is more about our stand against DRM.