Interval Tree: - Stores a set of intervals - Queries: "which intervals overlap with X?" - Best for: static set of intervals, many overlap queries Segment Tree: - Stores values at positions - Queries: range queries and updates on positions - Best for: array operations, range sum/min/max Overlap: When you have intervals AND need position-based queries, you might use both.
The sweep line technique often uses segment tree internally. Choose interval tree when the primary objects are intervals. Choose segment tree when the primary objects are positions.