NEW YORK (AP) — Facebook is introducing hashtags, the number signs used on Twitter, Instagram and other services to identify topics being discussed and allow users to search for them.

Facebook Inc. said in a blog post Wednesday that users will be able to click a hashtag to see a feed of discussions about a particular topic. For example, typing a number sign in front of "ladygaga" or "sunset" will turn the words into a link that users can click on to find posts about Lady Gaga or sunsets.

Facebook said hashtags are a first step toward making it easier for users to find out what others are discussing. The company is not giving exact details about other tools it might introduce. If Twitter's use of hashtags is any indication, Facebook will likely incorporate them into its advertising business.

"We'll continue to roll out more features in the coming weeks and months, including trending hashtags and deeper insights, that help people discover more of the world's conversations," wrote Greg Lindley, product manager for hashtags, in the post.

The hashtags will conform to users' privacy settings — so putting a hashtag in a post that's only visible to your friends won't make it show up for anyone other than your friends.

Facebook said it will make the clickable hashtags available to users in the coming weeks, beginning on Wednesday. Though hashtags haven't worked on Facebook until now, many people were using them anyway, having grown accustomed to them on Twitter, Instagram and elsewhere.

Using hashtags will help users gain a larger view of what others are talking about, Lindley said.