Depth-First Search

## How Depth-First Search Works

DFS explores as far as possible along each branch before backtracking. It uses a stack (or recursion) to track nodes.

### Algorithm Steps:
1. Start at the source node
2. Mark current node as visited
3. Recursively visit each unvisited neighbor
4. Backtrack when no unvisited neighbors remain
5. Repeat until all reachable nodes are visited

### Key Characteristics:
- **Uses Stack**: Last-In-First-Out (LIFO) or recursion
- **Path Finding**: Good for finding any path
- **Memory Efficient**: Uses less memory than BFS for wide graphs