> For the complete documentation index, see [llms.txt](https://docs.probly.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.probly.com/get-started/readme.md).
# What is Probly?
## Overview
**Probly — before it happens.** Trade real-world outcomes by buying **YES** or **NO** shares on a question. Prices reflect the market's view of how likely each side is to win.
> Buy **YES** at **15¢** on *"Will BTC reach $100k this week?"* The price implies a **15% chance**. If it happens, each share redeems for **$1.00** — turning **$0.15** into **$1.00** (**$0.85 profit** per share). If not, the shares settle at **$0**.
## How a Share Works
Every market asks a yes/no question. You can buy two things:
* A **YES share** — worth **$1.00** if the event happens, **$0** if not
* A **NO share** — worth **$1.00** if the event doesn't happen, **$0** if it does
Since exactly one side will be right, **1 YES + 1 NO = $1.00** at all times.
Three rules follow from this:
* **YES price + NO price ≈ $1.00.** YES at 60¢ ⇒ NO ≈ 40¢.
* **Price = implied probability.** YES at 60¢ ⇒ the market sees a **60% chance**.
* **Prices stay between 1¢ and 99¢** — closer to 99¢ means more likely; closer to 1¢ means less.
## How Trading Works
1. **Pick a market** — Crypto, sports, politics, and more.
2. **Buy YES or NO** at the current price.
3. **Hold or sell early** — Sell anytime before the deadline to lock in profit or cut losses.
4. **Settle automatically** — At resolution, winning shares pay **$1.00** and losing shares go to **$0**. USDC lands in your account; no claim step needed.
## At a Glance
| | |
| --------------------- | ---------------------------------------------------------------- |
| **Collateral** | USDC |
| **Share price range** | **1¢ – 99¢** ($0.01 – $0.99) |
| **Payout on win** | $1.00 per share |
| **Payout on loss** | $0 per share |
| **Market cycles** | 5-minute, 15-minute, hourly, daily, weekly, and long-form events |
## Where to Next
* [Making Your First Trade](/get-started/first-trade.md) — Get trading in minutes.
* [Trading Overview](/markets-and-trading/overview.md) — How the order book works.
## Join the Community
Chat with traders and the Probly team on [Discord](https://discord.gg/H82vHXEW) or [Twitter](https://x.com/ProblyHQ).
Need help? Use the **support** channel in the footer at [probly.com](https://probly.com), or reach out at ****.
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