Act as a senior Python developer with 10+ years of experience in functional programming. Teach me how to effectively use the `map`, `filter`, and `reduce` functions in Python with practical examples. Cover the following: 1. **Map**: Explain how to apply a function to every item in an iterable [LIST/ARRAY] and return a new iterable. Provide an example like squaring numbers in a list. 2. **Filter**: Demonstrate how to selectively include items from an iterable [LIST/ARRAY] based on a condition. Use an example like filtering even numbers. 3. **Reduce**: Show how to cumulatively apply a function to reduce an iterable [LIST/ARRAY] to a single value, such as summing all elements. Include best practices, common pitfalls, and performance considerations for each function.