According to the creator, Ruby was influenced by Perl, Smalltalk, Eiffel, Ada, BASIC, and Lisp.

So I decided to make it.Matsumoto describes the design of Ruby as being like a simple Lisp language at its core, with an object system like that of Smalltalk, blocks inspired by higher-order functions, and practical utility like that of Perl.

[11] The name "Ruby" originated during an online chat session between Matsumoto and Keiju Ishitsuka on February 24, 1993, before any code had been written for the language.

[13] Matsumoto later noted a factor in choosing the name "Ruby"–it was the birthstone of one of his colleagues.

[14][15] The first public release of Ruby 0.95 was announced on Japanese domestic newsgroups on December 21, 1995.

Already present at this stage of development were many of the features familiar in later releases of Ruby, including object-oriented design, classes with inheritance, mixins, iterators, closures, exception handling and garbage collection.

In early 2002, the English-language ruby-talk mailing list was receiving more messages than the Japanese-language ruby-list, demonstrating Ruby's increasing popularity in the non-Japanese speaking world.

Ruby 1.8 was initially released August 2003, was stable for a long time, and was retired June 2013.

[31] Ruby 2.2.0 includes speed-ups, bugfixes, and library updates and removes some deprecated APIs.

[33][34][35] Features that were made obsolete or removed include callcc, the DL library, Digest::HMAC, lib/rational.rb, lib/complex.rb, GServer, Logger::Application as well as various C API functions.

[36] Ruby 2.3.0 includes many performance improvements, updates, and bugfixes including changes to Proc#call, Socket and IO use of exception keywords, Thread#name handling, default passive Net::FTP connections, and Rake being removed from stdlib.

[39] Other notable changes include: A few notable changes in Ruby 2.5.0 include rescue and ensure statements automatically use a surrounding do-end block (less need for extra begin-end blocks), method-chaining with yield_self, support for branch coverage and method coverage measurement, and easier Hash transformations with Hash#slice and Hash#transform_keys On top of that come a lot of performance improvements like faster block passing (3 times faster), faster Mutexes, faster ERB templates and improvements on some concatenation methods.

A few notable changes in Ruby 2.7.0 include pattern Matching (experimental), REPL improvements, a compaction GC, and separation of positional and keyword arguments.

To achieve 3x3, Ruby 3 comes with MJIT, and later YJIT, Just-In-Time Compilers, to make programs faster, although they are described as experimental and remain disabled by default (enabled by flags at runtime).

[40] Ractor is light-weight and thread-safe as it is achieved by exchanging messages rather than shared objects.

[42] It includes YJIT, a new, experimental, Just-In-Time Compiler developed by Shopify, to enhance the performance of real world business applications.

Additionally, improvements in memory usage, the introduction of an M:N thread scheduler, and updates to the standard library contribute to a more efficient and developer-friendly Ruby ecosystem.

[45] At a Google Tech Talk in 2008 he said, "I hope to see Ruby help every programmer in the world to be productive, and to enjoy programming, and to be happy.

Matsumoto has said his primary design goal was to make a language that he himself enjoyed using, by minimizing programmer work and possible confusion.

He has said that he had not applied the principle of least astonishment (POLA) to the design of Ruby;[47] in a May 2005 discussion on the newsgroup comp.lang.ruby, Matsumoto attempted to distance Ruby from POLA, explaining that because any design choice will be surprising to someone, he uses a personal standard in evaluating surprise.

Ruby is object-oriented: every value is an object, including classes and instances of types that many other languages designate as primitives (such as integers, Booleans, and "null").

Though Ruby does not support multiple inheritance, classes can import modules as mixins.

One of the differences from Python and Perl is that Ruby keeps all of its instance variables completely private to the class and only exposes them through accessor methods (attr_writer, attr_reader, etc.).

As invocation of these methods does not require the use of parentheses, it is trivial to change an instance variable into a full function, without modifying a single line of calling code or having to do any refactoring achieving similar functionality to C# and VB.NET property members.

Ruby's design forces all instance variables to be private, but also provides a simple way to declare set and get methods.

The standardized and retired Ruby 1.8 implementation was written in C, as a single-pass interpreted language.

As of 2018[update], there are a number of alternative implementations of Ruby, including JRuby, Rubinius, and mruby.

The reference implementation, JRuby, and Rubinius[60] are all able to run Rails unmodified in a production environment.

Matsumoto originally developed Ruby on the 4.3BSD-based Sony NEWS-OS 3.x, but later migrated his work to SunOS 4.x, and finally to Linux.

Modern Ruby versions and implementations are available on all major desktop, mobile and server-based operating systems.