What are the main principles and features of using asynchronous methods in programming?

Asynchronous methods allow performing operations without blocking the main thread of execution. This is especially useful when working with input/output, network requests, or long computations.

Main principles:

• The method returns an object, such as Future, Promise, or Task, which represents the result of the operation.
• You can continue executing other tasks while the asynchronous operation is not completed.
• After completion, a callback is called or await is used to obtain the result.

Example in Python using async/await:

import asyncio

async def fetch_data():
    await asyncio.sleep(1)  # simulate delay
    return 'Data received'

async def main():
    result = await fetch_data()
    print(result)

asyncio.run(main())