Zero-party data is information the customer actively chooses to share with your brand. It includes the kind of personal details a shopper might share with a sales representative, such as what they're shopping for, their age and gender, and the best ways to get in touch with them.

Consumers are becoming increasingly aware-and wary-of how some companies track, sell, and buy their online data and use it to target them for aggressive sales and marketing pitches. Governments are cracking down by limiting how companies can collect and use customer data. And companies, including Apple and Google, are making it easier to opt out of being tracked.

As privacy becomes more and more important to consumers, intentionally proffered information is all the more valuable to marketers. Here's what you need to know about zero-party customer data, how to collect it, and how to put it to use for your brand.