Projects and Libraries.

In previous chapters we've looked at and worked with Ruby from a low-level perspective by working directly with classes, objects, and functions. Each line of code we've used in the small projects so far has been written specifically for that project from scratch. In this chapter, we'll look at how to build larger projects with Ruby, and how to reuse code written previously. Finally, we'll look at how to use code already written and prepared by other developers within your own applications, so that you don't need to reinvent the wheel every time you create a new program. [ABSTRACT FROM AUTHOR]