A quick overview of how to install a library in the Arduino IDE
To check if a library is installed, go to Sketch -> Include Library.
In the menu, if you do not see the library is it not installed. For example in this case we are looking for the Adafruit NeoPixel Library which is installed
To install a new library, go to Sketch -> Include Libraries -> Manage Libraries
In the Manage libraries popup/sidebar search for the library you want to install and when you find it, click the install button.
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