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About Me
- Jenelle
- I'm a first-semester MLIS student at the University of Pittsburgh. Last spring I graduated from the University of Pittsburgh with a BA in History/Political Science. My interests in Library Science include Reference Services and Community/Public Services.
1 comment:
Here is my understanding:
Direct access is when you are given an exact location to look at, a memory address in the case of computers, or, like the example in class, a page number in a book. With direct access you know exactly where to go, and so can just skip straight there, ignoring all other information.
In the case of sequential access, you have no specific marker of the location you need. I think someone gave the example of a scroll: unlike a book, you must read through it until you find what you are looking for. I guess this would be the same for a book without an index or page numbers. I believe, in the case of computers, that the old reals of tape used for storage would be considered sequential. The computer has to start reading the tape from the beginning and read everything until it finds what it needs (I hope someone will correct me if I am wrong there; I do not know exactly how these work, and I know this is a major simplification).
With a hard drive, the computer knows the memory address of a file, and so can find it almost immediately (direct access). It does not need to search for it (that would be sequential access).
I hope that made sense.
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