Ruby comes with a rich standard library that includes many packages for various functionalities. Some of the commonly used standard library packages in Ruby are:

  1. date: Provides classes for working with dates and times.
  2. json: Provides support for working with JSON data.
  3. net/http: Provides classes for working with HTTP requests and responses.
  4. openssl: Provides support for SSL/TLS encryption.
  5. csv: Provides support for reading and writing CSV files.
  6. fileutils: Provides classes for working with files and directories.
  7. uri: Provides support for parsing and manipulating URIs.
  8. socket: Provides classes for working with sockets.
  9. thread: Provides classes for working with threads.
  10. zlib: Provides support for compressing and decompressing data using the zlib library.

These are just a few examples of the many standard library packages available in Ruby.