Sequential Access
Indicates that data cannot be accessed without having to look through all earlier data first, in order. This term is best illustrated by example. A video tape and a cassette tape are sequential access devices. If you want to access a part in the middle of the video tape, you need to fast forward through everything up until that point. You cannot go directly to the middle of the tape. If you want to start at the beginning of the tape, you need to rewind.