Definition - What does Random Access mean?
In computer science, random access is the capability to have access to any item from a given population of elements at random. Random access is the opposite of sequential access, as sequential access locates elements by beginning at a particular predefined location and then traversing through all of the information in order to find the given item. Random access has gained interest due to the fact that one can retrieve a record irrespective of the position in which it is located.
Random access is also known as direct access.
Techopedia explains Random Access
When it comes to data structures, random access theoretically is the ability to access any element in a list regardless of the location in the list or the size of the list. However, apart from arrays there are only a few data structures which are capable of supporting random access. Random access is also used in algorithms such as integer sorting and binary search. One of the unique features of random access is that any required record can be accessed immediately on demand and access time is similar for a remote element as it would be for a nearby element. In order to decide whether the data needs to be accessed sequentially or randomly, the workload pertaining to the specific device must be analyzed.
In many electronic devices, accessing data sequentially works faster than accessing the data at random, mostly due to the manner in which the disk hardware has been designed. The seek operation, in most cases, takes a larger number in case of random access compared to sequential access. Another disadvantage associated with random access is the higher possibility of an emergence of a bottleneck between the different processes, activities and resources in the particular system.