Getting around

PaperDesk is a practice exchange. The buttons work like a trading desk. The money is credit you add on Home. A balance of zero just means you have not added any yet.

There is one price, SOL in USD, and two ways to trade it.

• Spot is buying and selling the coin. Buy spends USD and gives you SOL. Sell spends SOL and gives you USD.
• Perps is a bet on that price. Long profits if SOL rises. Short profits if it falls. You put up USD as a deposit. You do not receive the coin.

Start on Spot. Perps uses leverage, so a small price move can use up the deposit.

1. Open Home. The right side is your paper wallet.
2. Next to USD, click Add. Type a whole number, such as 10000, then Confirm. That USD is available on both Spot and Perps.
3. The big number is available: free to use. Locked is set aside for an open order, or for a perp deposit. Right after you add credit, locked is zero.
4. Open Spot. Leave Buy selected. Click Mid to copy a price near the middle of the book, or click a price in the book itself. Quantity is how many SOL you want.
5. Press Buy SOL. If someone is already selling at your price or lower, the order fills and your SOL balance goes up. If every seller is higher, the order waits, and the USD it needs stays locked until it fills or you press Cancel.
6. The list under the chart is that order. Orders is the same list with the full history.

To practice a sell, Add some SOL on Home the same way. SOL is only spent on Spot. Perps uses USD.

Spot and Perps use the same layout. Once you can name the four areas, both pages read the same way.

Chart

Recent prices, drawn as candles. Each candle is a slice of time.

Order book

Waiting buy orders (bids) and sell orders (asks). The closest prices meet in the middle. Click a price to copy it into the form.

Ticket

The order form. Spot says Buy or Sell. Perps says Long or Short. You set a price and a size, then submit.

Bottom strip

Spot lists open and recent orders. Perps adds a Position tab next to Orders.

The top of the page shows the latest price and whether the live feed is connected. When the feed returns, the book fills back in.

Spot swaps your practice USD and SOL. A buy can only spend the USD you already have available.

• Buy spends USD and adds SOL.
• Sell spends SOL and adds USD. Add SOL on Home first if your SOL balance is zero.
• The form is a limit order. It trades at your price or a better one. A buy at 140 fills when a seller is at 140 or lower. If every seller is higher, your buy waits on the book.
• Mid copies the halfway point between the best buy and the best sell. BBO copies the best price on your side.

Leave IOC and FOK unchecked for a first trade. The order then stays open until it fills or you cancel it. IOC fills whatever it can right now and cancels the rest. FOK fills the whole quantity now, or cancels the whole order.

An open order locks the USD or SOL it needs. Cancel sits on the order row while the status is still open.

A perp is a price bet paid in USD. Long profits when SOL rises. Short profits when it falls. Your SOL balance does not change.

• You need available USD. That USD is the margin, a deposit held while the position is open.
• Leverage is the slider from 1x to 20x. At 5x, a position worth about 500 USD locks about 100 USD. The same price move is a larger gain or loss, and you are closer to liquidation.
• Est. margin on the form is the USD that locks if the order fills. The button reads Long or Short plus the leverage, such as Long 5x.
• The Position tab shows side, size, entry price, margin, unrealized profit or loss, and the liquidation price. Unrealized is the result if you closed at the current mark. It is not in your available balance yet.
• Mark price is the price used for that profit and for liquidation. It is the middle of the book, or the last trade when the book has no middle.
• Funding is a small USD payment between longs and shorts. On this demo it runs about once a minute. When the rate is positive, longs pay shorts.

To shrink a long, submit a Short. To shrink a short, submit a Long. If losses use up the margin cushion, the position is closed for you. That close is a liquidation.

Home shows a short recent list. Orders is the full history. Click a row for the average fill price and each fill. Filters cover market, side, type, and time.

Pending, Accepted, Open

The order is on its way, or waiting on the book. You can usually cancel it.

Partial

Some of the size traded. The rest is still open.

Filled

The whole size traded. Nothing left to cancel.

Cancelled

You stopped it, or an IOC or FOK rule cancelled what could not trade immediately.

Rejected or Failed

It never traded. The row can include a reason. A common one is not enough available balance.

Order book

The live list of buy and sell orders waiting to trade.

Bid and ask

A bid is a waiting buy. An ask is a waiting sell.

Fill

One matched piece of your order, at a price and a size. A large order can fill in several pieces.

Available and locked

Available is free to spend. Locked is reserved for an open order or for perp margin.

Limit order

An order that trades only at your price or a better one, and waits on the book until then.

Mid and BBO

Mid is halfway between the best bid and the best ask. BBO is the best price on your side of the book.

IOC and FOK

IOC fills what it can immediately and cancels the rest. FOK fills the entire size now, or cancels the order.

Margin

The USD deposit a perp holds while the position is open.

Leverage

How large the position is compared with the margin. 5x means the position is about five times the USD you lock.

Notional

Price times size: the USD value of the order before leverage.

Mark price

The perp price used for profit and for liquidation checks.

Liquidation

An automatic close when losses have used up the margin cushion.

Funding

A small scheduled payment between longs and shorts.

For the path behind a click — the matching engine, the order handoff, and how charts are stored — see System.