Tehtehred downloads are sometimes called limited downloads. A tethered download is a digital file that is delivered electronically to a computer or other device to reside there on a limited basis.
There are two types of thethered downloads: time-limited download (for example, the song resides on the computer for 30 days) and use-limited download (for example, the song can be heard 12 times before it can no longer be played).