So far your programs have done the same thing every time. With input, a program can ask the person running it a question, wait for an answer, and use it:

name = input("What is your name? ")
print("Hello,", name)

Press Run. The program stops at input and waits. Type a name in the console and press Enter, and the program carries on with what you typed stored in name.

The text inside input(...) is the prompt, shown to the user before they type. Notice the space at the end of "What is your name? ": without it, the answer would be squashed right up against the question mark.