Information should be organized and presented in a useful order. Depending on the task and the user community, different organizing principles can be used: chronological, alphabetical, sequential, functional, proximity, frequency of use, or level of importance. Information needs to be organized into logical groups. When the information describes how to perform a complex task, the order of the instructions should mirror the order in which the sub tasks need to be performed. When enumerating items, use numbers not letters, and separate the numbers clearly from the text.