A campaign is an organized effort to achieve a specific goal, usually involving a series of planned actions over time. When a candidate runs for office, their campaign includes giving speeches, meeting voters, running advertisements, and explaining their ideas. When a charity launches a fundraising campaign, they organize events, send letters, and ask people to donate.

Today we still use it in military history: generals plan campaigns to achieve military objectives. But the word has spread far beyond warfare.

In advertising, companies run campaigns to sell products or change how people think about their brand. Schools might have a campaign to encourage recycling or reading. You might even campaign for something yourself, like organizing a petition drive or repeatedly asking your parents for a pet (though they might call that nagging!).

What makes something a campaign rather than just a single action? A campaign has a clear goal, happens over time, involves multiple connected efforts, and usually tries to persuade or influence people. Running one advertisement isn't a campaign, but running dozens of coordinated ads over several months is.