The `__lt__` method in Python is a special function that allows you to define the behavior of the less-than operator (`<`) for custom objects. When you implement this method in a class, you can specify how instances of that class should be compared to each other based on specific attributes or criteria. This makes it easier to sort and compare objects in a meaningful way. For example, if you have a class called Person with an attribute like age, you can implement `__lt__` to compare two Person objects based on their ages. This way, using the less-than operator will yield intuitive results, enhancing the usability of your custom classes.