**1. How does a set differ from a sequence?**

In a set such as {1,2, 3, 4} the order of the members of the set is not important. e.g. {1, 2, 3, 4} = {4, 3, 2, 1}

In a sequence <1, 2, 3, 4, ...> the order of the members of the sequence has to remain the same. <1, 2, 3, 4, ...> ≠ <4, 3, 2, 1, ...>

**2. Why do we need to study sets?**

Sets offer a convenient way to organise items and can be very useful for illustrating solutions to equations and inequations, solving probability problems and logic puzzles.