Collections can consist of lists, sets, or maps. There is a lot of data that we can store in collections. Naturally, we need to use this data or perform modifications on this data depending on the program requirement.
We need to iterate through the data that is stored in these collections. This is where the concept of Iterator comes into the picture.
The iterators are used to provide users a uniform way of accessing collections in a sequential manner. Whatever type of collection we are using, we always need to traverse through the elements of these collections to fetch the data or make any modifications to that data.
