User guides: paper or online?

Before we discuss whether documentation is better on paper or online, we define the following terms:

Frequently, people need a user guide when they start to work with software. For readers, a printed user guide has the following advantages compared to an online user guide:

Sometimes, people need both reference information and instructions for tasks. A good practical combination is to supply a printed (or printable) software user guide for instructions, and context-sensitive online help for reference information.

Sometimes, an online user guide is useful. For example, if people do not need conceptual information and if the tasks are simple, then an online user guide is an effective way of helping people to use software.