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README.md

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 [![Build Status](https://travis-ci.org/appium/ruby_lib_core.svg?branch=master)](https://travis-ci.org/appium/ruby_lib_core)
 
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+This library is a Ruby client for Appium.  The gem is available via [appium_lib_core](https://rubygems.org/gems/appium_lib_core).
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+This library wraps [selenium-webdriver](https://github.com/SeleniumHQ/selenium/wiki/Ruby-Bindings) and adapts WebDriver APIs for Appium. [ruby_lib](https://github.com/appium/ruby_lib) calls all of Appium/Selenium related APIs via this core library. It works instance based driver.
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 # Documentation
 
 - http://www.rubydoc.info/github/appium/ruby_lib_core