Internet Usage is the amount of information transferred over your internet connection (i.e. web browsing, checking email, downloading and uploading files, streaming audio and video, etc.). Different online activities transfer different amounts of information. All the devices connected to the internet within your home contribute to your usage including desktop computers, notebook computers, smart phones, tablet computers, iPods and gaming consoles.
This depends on what you do on the internet and the size of the files you are downloading or uploading. 250 GB would equate to approximately, 64,000 songs per month, 300 standard definition movies per month or 80 high definition movies per month.