Sequential Access Memory
An access time varies depending on location when using a sequential-access storage device since the arrival at the desired storage place is preceded by sequencing via other locations. In other words, we can only recover data from a sequential-access device in the order that it was originally saved.
In this type of memory, if we need to access an address that is out of order, in this case, we can reach it only by searching through all the addresses which are stored before it. For instance, we cannot access data stored at the last few locations until we have traversed all preceding locations in the sequence.
This is analogous to a music tape cassette. For example, if there are 100 songs recorded on a music tape cassette and we want to listen to the 50th song, then we must first listen to 49 songs coming before it. In this, we can use the "fast forward" option on the player for quickly pass the 49 songs, but the first 49 songs are still accessed, although, not fully played.
Magnetic Tape is an example of a sequential access storage device.
Advantages
i). Sequential access is well-suitable for processing large volumes of data that are stored sequentially.
ii) Sequential access storage devices are more reliable and cost-effective for certain applications.
iii) It's often more efficient to read or write data sequentially in one continuous stream, as opposed to seeking random locations.
iv) Sequential access devices are often used for streaming applications, such as playing audio or video files.
Disadvantages
i) The main disadvantage of sequential access is that it requires going through all the data that came before it in order to reach a given data point.
ii) It is not efficient if you need to access data at arbitrary locations.
iii) Sequential access is not suitable for interactive workloads where users need to quickly jump between different pieces of information.
