Divide and conquer is an algorithmic strategy for solving large problems by recursively breaking them into smaller, self-similar subproblems, solving those, and combining their solutions. It's applicable when subproblems are identical to the original and a method exists to combine their solutions. Examples include binary search and quicksort. Recurrence relations are used to analyze the time complexity of these recursive algorithms. This segment clarifies a critical aspect of the divide-and-conquer strategy. It emphasizes that the subproblems resulting from the division must be of the same type as the original problem. The speaker uses the example of sorting versus a workshop organization to illustrate this point, highlighting that only when subproblems mirror the original problem's nature can the divide-and-conquer approach be effectively applied. This distinction is crucial for understanding the applicability and limitations of this algorithmic strategy.