Your First Look at a Chart and an Order Book

11.1 The trading screen

Mint opened the advanced trading screen on an exchange for the first time and immediately closed it again. Coloured bars, flickering numbers, two columns of red and green prices, buttons labelled "limit," "market," and "stop."

"I'm not ready for this," Mint said.

"You are," said Hash. "It looks complicated, but it's really just two things: a chart showing where the price has been, and an order book showing who wants to trade right now. Let's take them one at a time."

This chapter is a first introduction. The Technical Analysis module will go much deeper into reading charts.

11.2 Candlesticks

Most crypto charts use candlesticks. Each candle summarises price movement over a fixed period of time, which could be one minute, one hour, one day, or any other timeframe you choose.

Every candle shows four prices:

Open: the price at the start of the period. High: the highest price during the period. Low: the lowest price during the period. Close: the price at the end of the period.

The thick part of the candle is the body, stretching from the open to the close. The thin lines above and below are the wicks (or shadows), showing the high and low.

If the close is higher than the open, the price rose, and the candle is usually green. If the close is lower than the open, the price fell, and the candle is usually red.

Here's a one-hour BTC candle described in numbers.

	Price
Open	$100,000
High	$101,200
Low	$99,500
Close	$100,800
Colour	Green, because it closed above the open

Reading this candle: during that hour, the price dipped as low as $99,500, rallied as high as $101,200, and ended at $100,800, up $800 from where it started.

"So a long wick means the price went somewhere and came back?" Mint asked.

"Exactly," said Hash. "A long lower wick means sellers pushed the price down, but buyers pushed it back up. Candles tell little stories about the fight between buyers and sellers."

11.3 Timeframes

The same market looks completely different on different timeframes. A one-minute chart might show wild swings, while the daily chart shows a calm, steady trend. Neither is wrong. They just answer different questions.

As a rough guide, long-term investors usually look at daily and weekly charts. Swing traders, who hold positions for days to weeks, look at four-hour and daily charts. Day traders look at one-hour charts and below. A common beginner mistake is staring at very short timeframes, where moves are mostly noise.

Below the price chart, most screens show volume bars, the amount traded during each period. A big price move on high volume is generally considered more meaningful than the same move on low volume.

11.4 The order book

Now for the second half of the screen. The order book is a live list of all the waiting buy and sell orders for a trading pair.

Bids are buy orders: people offering to buy at a certain price, usually shown in green.

Asks (or offers) are sell orders: people offering to sell at a certain price, usually shown in red.

Here's a simplified BTC order book.

Side	Price	Amount (BTC)
Ask	$100,050	1.2
Ask	$100,020	0.8
Ask	$100,010	0.5
Spread	$10
Bid	$100,000	0.6
Bid	$99,990	1.0
Bid	$99,950	1.5

The highest bid is $100,000. The lowest ask is $100,010. The gap between them, $10, is the spread. In liquid markets, the spread is tiny. In illiquid markets, it can be large, which means you lose more simply by entering and exiting a trade.

11.5 Market orders and limit orders

There are two basic ways to place an order.

A market order says: "Fill my order right now at the best available price." It's fast and certain to execute, but you don't control the exact price.

A limit order says: "Fill my order only at this price or better." You control the price, but your order might not fill if the market never reaches it.

Let's see what happens if Mint places a market order to buy 1 BTC using the order book above. Mint's order eats through the asks, starting from the cheapest.

Filled from	Price	Amount	Cost
First ask	$100,010	0.5 BTC	$50,005
Second ask	$100,020	0.5 BTC	$50,010
Total		1 BTC	$100,015

Mint's average price was $100,015, slightly above the best ask, because the first level didn't have enough BTC. This is slippage again, the same idea from Chapter 8, now on an order book. In thin markets, a large market order can walk through many levels and get a much worse average price.

If Mint instead placed a limit order to buy 1 BTC at $100,000, the order would join the bids and wait. If a seller comes along willing to sell at $100,000, Mint's order fills. If the price rises instead, Mint's order sits unfilled.

Remember maker and taker fees from Chapter 7? A market order is a taker order, because it takes existing liquidity. A limit order that waits in the book is a maker order, because it adds liquidity. That's why limit orders often have lower fees.

Chapter 11 · A candlestick and an order book

On the left, a single up candle shows open $100,000, high $101,200, low $99,500, and close $100,800, with the body between open and close and wicks to the high and low. On the right, an order book lists asks above the spread and bids below it; a 1 BTC market buy consumes all 0.5 BTC at the $100,010 level and 0.5 of the 0.8 BTC at the $100,020 level for an average fill of $100,015.

11.6 Stop orders

One more order type is worth knowing from day one. A stop order (often called a stop-loss) triggers an order once the price reaches a level you set. For example: "If BTC falls to $95,000, sell my position."

Stop orders help limit losses when you can't watch the market, which matters in a market that never closes. But in fast markets, a stop that triggers a market order can fill at a worse price than you set. We'll cover how to use them properly in the Risk Management module.

Order type	You control	Main risk
Market	Speed	Worse price than expected, especially in thin markets
Limit	Price	Order may never fill
Stop	When you exit or enter	Can fill at a worse price during sharp moves

11.7 Reading the room

Node had been studying the order book. "What if someone puts a huge buy order just below the price? Does that mean the price won't fall?"

"It might act as support," said Hash. "Or it might be fake. Large orders can be placed to influence other traders and then cancelled before they fill. The order book shows intentions, not commitments."

This practice, called spoofing, is illegal in many regulated markets but happens in crypto. Treat the order book as useful information, not a promise.

11.8 Try it yourself

Open the BTC chart on any exchange or charting site. Switch between the one-minute, one-hour, and daily timeframes and notice how different the market looks. Pick one daily candle and write down its open, high, low, and close.

Then look at the order book for a major pair like BTC/USDT and a much smaller token. Compare the spreads. Calculate how much BTC you could buy before the price moves 0.1% in each market. You'll see the difference between deep and thin liquidity immediately.

Key takeaways from this chapter

1. Candlesticks summarise price movement over a period using the open, high, low, and close.
2. Green candles close above their open, red candles close below. Wicks show the extremes reached during the period.
3. The same market looks very different across timeframes, and short timeframes are mostly noise.
4. The order book lists bids (buy orders) and asks (sell orders). The gap between them is the spread.
5. Market orders fill immediately but can suffer slippage. Limit orders control price but might not fill.
6. Stop orders help manage risk but can fill at worse prices in fast markets.
7. The order book shows intentions, not commitments. Large orders can be cancelled before they fill.