The Ruby Standard Library is a vast collection of classes and modules that you can require in your code for additional features.
Below is an overview of libraries and extensions followed by a brief description.
MakeMakefile
Module
used to generate a Makefile for C extensions
Information of your configure and build of Ruby
Package management framework for Ruby
Coverage
Provides coverage measurement for Ruby
Monitor
Provides an object or module to use safely by more than one thread
Extends ObjectSpace
module to add methods for internal statistics
PTY
Creates and manages pseudo terminals
Ripper
Provides an interface for parsing Ruby programs into S-expressions
Socket
Access underlying OS socket implementations
Abbrev
Calculates a set of unique abbreviations for a given set of strings
Base64
Support for encoding and decoding binary data using a Base64
representation
Benchmark
Provides methods to measure and report the time used to execute code
Bundler
Manage your Ruby application's gem dependencies
CGI
Support for the Common Gateway Interface protocol
CSV
Provides an interface to read and write CSV
files and data
Debugging functionality for Ruby
Delegator
Provides three abilities to delegate method calls to an object
DidYouMean
“Did you mean?” experience in Ruby
DRb
Distributed object system for Ruby
English
Provides references to special global variables with less cryptic names
ERB
An easy to use but powerful templating system for Ruby
FileUtils
Several file utility methods for copying, moving, removing, etc
Find
This module supports top-down traversal of a set of file paths
Provides delegation of specified methods to a designated object
GetoptLong
Parse command line options similar to the GNU C getopt_long()
IPAddr
Provides methods to manipulate IPv4 and IPv6 IP addresses
Interactive Ruby command-line tool for REPL (Read Eval Print Loop)
OptionParser
Ruby-oriented class for command-line option analysis
Logger
Provides a simple logging utility for outputting messages
Mutex_m
Mixin to extend objects to be handled like a Mutex
Net::HTTP
HTTP client api for Ruby
Observable
Provides a mechanism for publish/subscribe pattern in Ruby
Open3
Provides access to stdin, stdout and stderr when running other programs
OpenStruct
OpenURI
An easy-to-use wrapper for Net::HTTP
, Net::HTTPS and Net::FTP
PP
Provides a PrettyPrinter for Ruby objects
Implements a pretty printing algorithm for readable structure
PStore
Implements a file based persistence mechanism based on a Hash
Resolv
Thread-aware DNS resolver library in Ruby
RDoc
Produces HTML and command-line documentation for Ruby
Rinda
The Linda distributed computing paradigm in Ruby
SecureRandom
Interface for secure random number generator
Set
Provides a class to deal with collections of unordered, unique values
Shellwords
Manipulates strings with word parsing rules of UNIX Bourne shell
Singleton
Implementation of the Singleton
pattern for Ruby
Tempfile
A utility class for managing temporary files
Time
Extends the Time
class with methods for parsing and conversion
Timeout
Auto-terminate potentially long-running operations in Ruby
Extends the Dir
class to manage the OS temporary file path
TSort
Topological sorting using Tarjan's algorithm
Utilities to replace common UNIX commands
URI
A Ruby module providing support for Uniform Resource Identifiers
YAML
WeakRef
Allows a referenced object to be garbage-collected
BigDecimal
Provides arbitrary-precision floating point decimal arithmetic
Date
A subclass of Object
includes Comparable
module for handling dates
DateTime
Subclass of Date
to handling dates, hours, minutes, seconds, offsets
Digest
Provides a framework for message digest libraries
Etc
Provides access to information typically stored in UNIX /etc directory
Fcntl
Loads constants defined in the OS fcntl.h C header file
Fiddle
A libffi wrapper for Ruby
IO
Extensions for Ruby IO
class, including wait, nonblock and ::console
JSON
Implements Javascript Object
Notation for Ruby
NKF
Ruby extension for Network Kanji Filter
OpenSSL
Provides SSL, TLS and general purpose cryptography for Ruby
Pathname
Representation of the name of a file or directory on the filesystem
Psych
A YAML
parser and emitter for Ruby
Racc
A LALR(1) parser generator written in Ruby.
Readline
Provides an interface for GNU Readline
and Edit Line (libedit)
StringIO
Pseudo I/O on String
objects
StringScanner
Provides lexical scanning operations on a String
Syslog
Ruby interface for the POSIX system logging facility
WIN32OLE
Provides an interface for OLE Automation in Ruby
Zlib
Ruby interface for the zlib compression/decompression library
A test suite with TDD, BDD, mocking and benchmarking
Power Assert for Ruby.
Ruby build program with capabilities similar to make
A compatibility layer for MiniTest
An XML toolkit for Ruby
Family of libraries that support various formats of XML “feeds”
Support for the File
Transfer Protocol
Ruby client api for Internet Message Access Protocol
Ruby client library for POP3
Simple Mail Transfer Protocol client library for Ruby
Represents a mathematical matrix.
Prime numbers and factorization library
RBS is a language to describe the structure of Ruby programs
A type analysis tool for Ruby code based on abstract interpretation