Have there been cases of using type annotations in your projects?

Yes, type annotations were used in projects to improve code readability and facilitate static checking. For example, in Python, you can specify the types of function arguments and return values:

from typing import List

def greet(names: List[str]) -> None:
    for name in names:
        print(f"Hello, {name}!")

This helps tools like mypy detect type errors before running the program.