In Python, files are objects that represent a stream of data, typically stored on a storage device such as a hard drive. Python’s built-in “open” function allows us to open and manipulate files.

There are three basic operations used when working with files in Python:

1. Opening a file:
To open a file, we use the built-in “open” function which takes two parameters: the file path/name, and the mode in which we want to access the file. The mode can be “r” (read), “w” (write), “a” (append), or “x” (exclusive creation).

2. Reading from a file:
There are several ways to read data from a file in Python. We can use the “read” method to read the entire contents of a file as a string, or we can use the “readline” method to read a single line at a time. Alternatively, we can use a “for” loop to iterate over each line in the file.

3. Writing to a file:
To write data to a file, we use the “write” method. We can also use the “writelines” method to write a list of strings to a file.

Once we have finished working with a file, we need to close it using the “close” method. It is important to close files after working with them to ensure that all data is written to the file and that system resources are freed up.

Overall, files are an essential tool for reading and writing data in Python, and understanding how to work with them is a fundamental skill for any Python programmer.