How is Appium built?Appium is basically an HTTP server written in Node.js® that creates and handles webdriver sessions.
Appium architectureAs Appium is an HTTP server, its performs pretty much same as Selenium Webdriver server by
- Receiving request/commands from client libraries*
- Executes the command on the target devices/emulators
- Responds with an HTTP response
Client librariesAppium client libraries has different language bindings like