# Perpetual Futures

Meridian is an order-book perpetuals exchange with offchain matching and onchain settlement. It supports crypto markets and [mutualized perps (mPerps)](/trading/perpetual-futures/rwa-perpetuals) with cross or isolated margin.

Signed orders enter through the Trading API. Order and fill updates stream over WebSocket, and the exchange contracts record settled positions and balances. See [How the Exchange Works](/trading/perpetual-futures/exchange-architecture).

## Charges and Liquidation

* A [trading fee](/trading/perpetual-futures/fees) when an order fills.
* A [funding payment](/trading/perpetual-futures/funding-rates) when the hourly funding rate applies.
* A [position fee](/trading/perpetual-futures/position-fees) during a scheduled mPerp mark-price gap.

The applicable margin pool is eligible for [liquidation](/trading/perpetual-futures/liquidations) when its equity falls below maintenance margin. [Auto deleveraging](/trading/perpetual-futures/auto-deleveraging) applies if the liquidator account becomes insolvent.

## Documentation

* [How the Exchange Works](/trading/perpetual-futures/exchange-architecture)
* [Mutualized Perps](/trading/perpetual-futures/rwa-perpetuals)
* [Margining](/trading/perpetual-futures/margining)
* [Trading Fees](/trading/perpetual-futures/fees)
* [Position Fees](/trading/perpetual-futures/position-fees)
* [Order Types](/trading/perpetual-futures/order-types)
* [Positions](/trading/perpetual-futures/positions)
* [Funding Rates](/trading/perpetual-futures/funding-rates)
* [Market Specifications](/trading/perpetual-futures/market-specifications)
* [Liquidations](/trading/perpetual-futures/liquidations)
* [Auto Deleveraging](/trading/perpetual-futures/auto-deleveraging)
* [Subaccounts](/trading/perpetual-futures/subaccounts)
* [Price Oracles](/trading/perpetual-futures/price-oracles)
* [Self-Trade Prevention](/trading/perpetual-futures/self-trade-prevention)
* [Block Execution](/trading/perpetual-futures/block-execution)
* [Trading API](/developer-guides/trading-api)