Twitter on Thursday began letting advertisers target users with "promoted tweets" based on interests expressed at the globally popular one-to-many texting service.

Twitter also slashed to a penny the minimum opening bid in its auction-style ad-buying system.

"We're taking an important next step by allowing you to target your Promoted Tweets and Promoted Accounts campaigns to a set of interests that you explicitly choose," Twitter product management director Kevin Weil said in a blog post.

"When people discover offers and messages about the things they care about on Twitter, it's good for both marketers and users."

Twitter ad products tap into a "real-time interest graph" to target promoted "tweets," terse text messages, in hundreds of categories ranging from gardening and hobbies to pets and investing.

Factors that go into determining interests include which Twitter accounts people follow, such as sports teams or chefs.

The San Francisco-based firm boasts having 140 million active users.