Faraday is a modular HTTP client library for Ruby, designed to simplify calling external APIs from Rails applications. It uses a middleware architecture, allowing developers to easily add features such as logging, retries, authentication headers, and response parsing. 

To get started, add the gem to your Gemfile, choose an adapter like Net::HTTP or Typhoeus, and configure middleware in a connection object. 

Faraday supports Ruby 3+ and works seamlessly with Rails 6, 7 and 8. 

Alternatives include HTTParty for simplicity or the native Net::HTTP for minimal overhead.