Explain how to implement a Fenwick Tree (Binary Indexed Tree) step-by-step for efficient range queries and point updates. Cover the following: 1. [DATA_STRUCTURE] - Describe the underlying structure and why it's efficient (O(log n) operations). 2. [OPERATIONS] - Detail how to perform point updates (add a value to an index) and prefix sum queries (sum from 1 to [INDEX]). 3. [USE_CASE] - Provide a concrete example (e.g., solving a problem like 'Range Sum Queries' on [PLATFORM]). Include code snippets in [LANGUAGE] (e.g., Python/C++) with comments. Highlight common pitfalls (e.g., off-by-one errors) and optimization tips (e.g., 1-based indexing).