The Divide and Conquer method is an important part of the Binary Search. It helps break down the search process step by step.

1. How It Works:

• When using Binary Search, it takes a sorted list and divides it into two equal parts each time.
• If the item you're looking for is smaller than the middle value, it will look in the left half. If it’s bigger, it will search the right half.

2. How Fast It Is:

• Time complexity: This means how long it takes. For Binary Search, it’s $O(\log n)$, where $n$ is the number of items in the list.
• Space complexity: This talks about how much memory is needed. For the regular way of doing it, it's $O(1)$. If done in parts (recursively), it's $O(\log n)$.

3. When to Use It:

• You should only use Binary Search on a sorted list.
• It's really effective for big lists, usually when there are more than 10,000 items.