All the programs are executed in the RAM which is volatile means not permanent. In this type of memory the data can be shown till the program in this memory. Once program exits from RAM then those values cannot get again. This was the main disadvantage of the volatile memory. Then the concept of the file comes.
By using the files we can store our important data as well access any time. Let suppose if we want to enter large amount of data in program then it is difficult to type every time then it is easy to get data from file.
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