The itertools module is a standard library module in Python that provides a number of functions and classes for working with iterators. It can be helpful in day-to-day work by providing a number of common tasks that can be performed with iterators, such as:

• Creating iterators from lists, strings, and other iterables
• Combining iterators into new iterators
• Filtering iterators
• Sorting iterators
• Mapping functions over iterators
• Reducing iterators to a single value

The itertools module can also be used to create custom iterators, which can be useful for performing tasks that are not easily performed with standard iterators.