> For the complete documentation index, see [llms.txt](https://zeit-1.gitbook.io/zeit/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://zeit-1.gitbook.io/zeit/get-started/key-concepts.md).

# Key Concepts

Key terms used throughout the documentation.

| Term                                     | Definition                                                                                                                                                                                   |
| ---------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **Perpetual Prediction Vault (PPV)**     | An on-chain vault that holds and trades a portfolio of prediction-market positions and keeps the strategy running over time by rolling into new markets as older markets resolve or before.  |
| **PPV share / PPV token**                | An ERC‑20 token that represents a pro‑rata ownership claim on a vault’s assets and PnL (i.e., on its NAV). Shares are minted/burned during roll events at the current PPS.                   |
| **NAV (Net Asset Value)**                | The vault’s value in collateral terms (e.g., USDC): mark‑to‑market value of all open positions + idle collateral − accrued fees/obligations.                                                 |
| **PPS (Price Per Share)**                | The economic value of one PPV share: PPS = NAV ÷ total PPV shares outstanding. Used as the conversion price for minting/burning shares during a roll.                                        |
| **Mark‑to‑market**                       | Valuing open positions using current market prices (orderbook prices), rather than waiting for market resolution.                                                                            |
| **Roll / Epoch**                         | A discrete processing event where the vault sets PPS, and processes queued deposits and withdrawals at that PPS.                                                                             |
| **Batching**                             | Processing many deposits/withdrawals together in a roll (instead of instantly) to reduce per-user gas and to avoid pricing based on momentary orderbook conditions in thin markets.          |
| **High‑water mark (HWM)**                | The highest PPS previously reached at a fee checkpoint. Performance fees apply only to PPS above the HWM, so the same gains are not charged twice.                                           |
| **Fees**                                 | Two fee types: (1) Performance fee with HWM paid to the vault manager in vault shares, and (2) a small per‑trade protocol fee charged when the vault executes buys/sells (protocol revenue). |
| **Pending deposit / pending withdrawal** | A submitted deposit/withdrawal request that is queued and not yet settled in a roll (shares not yet minted for deposits; collateral not yet paid out for withdrawals).                       |
| **Price impact**                         | The difference between a “paper” price (e.g., mid) and the price achievable when actually executing size into the orderbook; higher when liquidity is thin.                                  |
| **Risks**                                | Key risks include market/volatility risk, liquidity & slippage risk, resolution/oracle risk (from underlying markets), execution risk, strategy/manager risk, and smart‑contract risk.       |