Tessell’s Availability Machine is billed in gigabyte-month (GiB-month). GiB-month is a measure of an Availability Machine’s storage along with the duration for which that storage is consumed. A duration of one month is counted as 730 hours. For example, if an Availability Machine’s size is a constant 1 GiB for the entire month (all 730 hours), its total size added over all the hours comes to 730 GiB. This Availability Machine is said to be billed for 1 GiB-month.