Use the built-in `open()` function to read and write files. Use modes like 'r' for reading and 'w' for writing, and remember to close the file afterward.

Reading and writing files in Python is a fundamental task that can be accomplished using the built-in open() function. The open() function takes two primary arguments: the filename and the mode. Common modes include:

• 'r' for reading (default mode)
• 'w' for writing (overwrites existing content)
• 'a' for appending

To read a file, use:

with open('file.txt', 'r') as file:
    content = file.read()

The with statement is recommended for file handling, as it ensures proper closure of the file even if an error occurs. For writing to a file:

with open('file.txt', 'w') as file:
    file.write('Hello, World!')

For large files, consider using readline() or iterating over the file object to read line by line, which is more memory efficient. By mastering file I/O in Python, you can effectively manage data storage and retrieval in your applications.