Although the video footage captured by your digital camcorder is recorded as long series of ones and zeros, it’s written on magnetic tape (which is still the best way to store the vast amount of information that digital video occupies). To turn that footage into a malleable form you can edit, you need to bring it from the camera’s tape to your hard disk. iMovie calls this process importing.
Before you start, make sure you have plenty of free space on your hard disk: importing a typical 60-minute MiniDV tape takes up roughly 13 gigabytes (GB) of hard disk space (1 second of DV video equals 3.6 MB). If you’re importing HD footage, plan on using about four times that amount of disk space.