If you have never used plt, this chapter contains the essential information you need to begin making your own plots with plt. The first section describes how plt commands are constructed; don't skip this section, because it introduces important concepts and terminology that are used throughout the book. A few notes on using plt without an X server follow in section 2.2. The chapter concludes with a tutorial, section 2.4, in which you create a simple plot and then produce several increasingly elaborate variations that illustrate a number of the most useful features of plt. Be sure to work through these examples, and then try making a few plots of your own before continuing.