# Block Explorer * X-Chain Scan is more than just a block explorer. It contains useful resources that developers can leverage for their dapps, such as the PostgreSQL database layer, GraphQL server and smart contract APIs. * X-Chain chain data Most apps require a fast and efficient data source for things that are not easily available over raw blockchain RPC, for example: Balances of all tokens that a user has list of token holders for a particular coin history of token trades on a DEX history of user’s interaction with a smart contract X-Chain Scan offers 3 solutions for various use cases: * GraphQL server for web apps PostgreSQL database for advanced apps and data analysis HTTP API for developers. * See All blocks and transactions. Interact with your contracts. Decode functions, events, and variables data. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://x-chain-1.gitbook.io/x-chain/block-explorer.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.