what is stream of data ?

In the context of iterators, the term "stream of data" refers to a sequence of elements that can be accessed one at a time. An iterator doesn't store all elements in memory at once; instead, it generates or retrieves each element as needed, which can be particularly useful when dealing with large datasets or when elements are generated on-the-fly.

For example, imagine a long list of numbers that you want to process one by one. Instead of loading the entire list into memory, an iterator allows you to access each number individually, process it, and then move on to the next one. This approach minimizes memory usage and can improve efficiency, especially for large or potentially infinite sequences.

def generate_numbers(limit):
    num = 0
    while num < limit:
        yield num
        num += 1

number_stream = generate_numbers(5)
for number in number_stream:
    print(number)

Here, generate_numbers produces a "stream of data" by yielding each number one at a time. The data (numbers) are accessed sequentially without all being stored in memory at once.