Standard Library

The Ruby standard library extends the foundation of the Ruby built-in library with classes and abstractions for a variety of programming needs, including network programming, operating-system services, threads, and more. These classes provide flexible capabilities at a high level of abstraction, giving you the ability to create powerful Ruby scripts useful in a variety of problem domains.

Many common tasks are performed by Ruby programmers all over the world. Some of these tasks include network access such as TCP/IP and CGI, OS access, database access, controlling processes with threads, numeric calculations, implementing design classes, and manipulating dates. These are used so frequently that they are included with all standard distributions of Ruby; when you access these classes and methods from your programs, they will be available from the Standard Library. Could you write these libraries yourself? Probably. Would you feel confident they have been exhaustively tested, optimized, and debugged? Usually not. The Standard Library is a great time saver. And as Ruby grows and evolves, so will its Standard Library, to everyone’s benefit.

Although not every library section will contain all these entries, the basic format for each section is as follows:

  • Required library

  • Example

  • Inherited class

  • Class methods

  • Instance methods

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