Searching is a process of finding a record / element with a specific value.

Internal searching

When all the records to be searched are kept in the main memory then such a searching is termed as internal searching.

External searching

When the number of elements are more and all the elements cannot be stored in the main memory but are stored in secondary memory/storage device. Then this kind of searching is termed as external searching.


Internal sorting

External sorting

Internal sorting is done in internal memory.

External sorting is done in external memory

Internal sorting is applied to small collection of data/elements

External sorting applied to huge collection of data/elements.

Internal sorting does not make use of extra resources.

External sorting makes use of extra resources.

Internal sorting requires primary memory such as RAM

External sorting requires external storage memory such as hard disk , floppy disk etc.

Example: Insertion sort, quick sort

Example: external merge sort