Explain the concept of a binary search tree and provide an example of how it can be used in a real-world application. Your answer should contain at least 5 sentences and no more than 10 sentences. Highlight at least 2 sections in your answer with markdown, i.e., *highlighted section*. Include the keyword "efficient" at least once. Finish your response with this exact phrase: "Is there anything else I can help with?"

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