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The charger cable is actually a USB cable that plugs into an electrical outlet adapter. You can remove the adapter by tugging the base of the connection away from the adapter until it slides out. If your charger cable doesn't have an electrical outlet adapter on it, skip this step. The rectangular USB end of the charger fits into a similarly shaped port on your computer.  If you're using a Mac laptop computer, it most likely doesn't have USB ports that fit the charger. You'll need to buy a USB-C to USB 3.0 adapter and then plug the adapter into one of the small USB ports on the side of the Mac. USB plugs only fit one way, so be sure to rotate the plug 180 degrees if it won't fit into the port. The iPad's charging port is at the bottom of the iPad's housing. If iTunes doesn't open automatically, double-click the iTunes app icon, which resembles a multicolored musical note on a white background. If you don't yet have iTunes installed on your computer, install it first. This will only appear if this is your first time connecting your iPad to your computer. You have successfully connected your iPad to your computer. You'll also need to click Continue on your computer if prompted.

Summary:
Remove the charger cable's electrical outlet adapter if necessary. Plug the USB end of the charger into your computer. Plug the charging end of the charger into your iPad. Open iTunes on your computer. Tap Trust on your iPad.