VirtualBox Guest Additions give our virtual machines extra features which can be very useful. These features range from being able to freely resize our virtual machine window to give it a more viewable size, to being able to drag files into and out of it.
To install guest additions click on Devices and Insert Guest Additions CD image. This will cause VirtualBox to go out and automatically download the correct version of the Guest Additions CD Image and insert it into your virtual machine.
Here we are presented with the Dialog to run the Guest Additions installer. Click Run to start the install process.
We are now presented with an Authentication window. Type in your user password and click Authenticate to continue.
The final step to finish the installation process of the VirtualBox Guest Additions is to reboot the virtual machine. Click on the Gear icon in the upper right hand corner. Choose Shutdown…
Next choose Restart to reboot the virtual machine.