> For the complete documentation index, see [llms.txt](https://docs.defi.app/knowledge-base/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.defi.app/knowledge-base/trade-and-earn/trade-perpetuals/faqs.md). # FAQs #### 1. **How Do Perpetuals Work?** Perpetual futures (or “perps”) are derivative contracts that let you speculate on an asset’s price indefinitely. There’s no expiration date, so you can hold any position as long as you have enough margin. To keep the contract’s price aligned with the asset’s actual (spot) price, perps use a mechanism called the **funding rate**, which is a regular payment exchanged between traders: * If the perpetual price is above spot, longs pay shorts. * If it’s below, shorts pay longs. Defi App performs the funding transaction every 8 hours. *** #### 2. **How Are Perps Implemented in DeFi App?** *** #### 3. **What Are Oracle Sources?** An oracle is a bridge between on-chain systems and off-chain data (specifically, price feeds). Because smart contracts can’t fetch external data on their own, oracles provide trustworthy, tamper-resistant pricing so protocols can handle derivatives, liquidations, and valuations. *** #### 4. **Which Oracle Sources Does DeFi App Use?** --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## 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, and the optional `goal` query parameter: ``` GET https://docs.defi.app/knowledge-base/trade-and-earn/trade-perpetuals/faqs.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. 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.