High-Frequency Trading Foundations

Lesson Promise

By the end of this lesson, you will understand what financial markets are, how order books work, how a market order gets filled, and why saving microseconds matters in trading.

Narration Draft

"Financial markets are systems that match buyers and sellers. An order book is a list of buy and sell orders organized by price. When a market order arrives, it 'sweeps' through the book from the best price, filling shares one level at a time. In high-frequency trading, every microsecond of latency means the difference between winning a trade and missing it."

Visual Sequence

1. Scene 1 — Order book diagram showing bids, asks, spread, and depth
2. Scene 2 — Trace animation of a market order sweeping through price levels
3. Scene 3 — Latency breakdown: decision → encode → network → exchange → match → confirm
4. Scene 4 — Taking vs making liquidity comparison

Companion Material

• Article: What Is a Financial Market?
• Article: Order Types and the Order Book
• Diagram: Order Book State
• Trace: Trace a Market Order
• Practice: Match Orders from a Feed
• Interview: What Is Trading Latency?
• Learning Path: HFT From the Ground Up