The Market Watch window in MT4 provides real-time information on financial instruments available for trading, such as currency pairs, commodities, and indices. It shows key data like bid and ask prices, spreads, and other details that traders can use to make informed decisions.

To open the Market Watch window, click "View" in the top menu and select "Market Watch”, or simply press Ctrl+M.

Some of the key features of the Market Watch include:

1. Price Quotes: Displays the bid (sell) and ask (buy) prices for various instruments.
2. Chart Access: You can open charts for specific instruments by right-clicking and selecting "Chart Window."
3. Depth of Market: Provides information about market liquidity at different price levels for certain instruments.
4. Symbol List: Allows you to customize the list of instruments visible by selecting or deselecting symbols.
5. Tick Chart: Displays the real-time price movements of the selected instrument.
6. Specification: Contains the terms of a trading symbol. To view the symbol properties, click "Specification" in its context menu in the "Market Watch" window.

For a detailed explanation of what Market Watch is, how to enable it, and how to use it, please watch the video below.