An economic calendar is a trading tool that lists scheduled economic events, data releases, central bank meetings, and policy announcements. It tells you when information likely to move markets is due.
An economic calendar usually shows the event time, country, currency, forecast, previous result, actual result, and expected impact. Listed events include inflation reports, employment data, GDP releases, interest rate decisions, retail sales, and manufacturing surveys.
An economic calendar schedules the news; it does not forecast the result or the price reaction. You use it to know when a release is due, then read the move from the forecast against the actual figure. Forex, CFD, stock, commodity, and index traders all watch it, because a single high-impact release can move several markets at once.
You see that the US Non-Farm Payrolls report is scheduled for 13:30 UTC.
You check the forecast and prepare for possible volatility in EUR/USD, USD/JPY, gold, and US stock indices.
If the jobs data comes in much stronger than expected, the US dollar can strengthen, because traders may expect tighter Federal Reserve policy.