Hashtags do more than add an ironic underscore to your tweets or Instagram posts. They can also connect you with a wider audience, including customers and contacts in your chosen market. Even if people don’t follow you, they do search for relevant hashtags (something Instagram just added), which means they’ll see what you post when you include key words.

Both Instagram and Twitter make it very easy to search via hashtag. On their websites, you can find the search boxes at the top of the screen, and in the mobile apps, you can search by navigating to the separate tab.

There are no hard and fast rules about how to use hashtags—it really depends on what you’re selling and what your business is. Still, you can pick up some ideas by looking at other accounts in your field and seeing what words they choose. One rule you should follow is to avoid hashtag overload. A post filled entirely with hashtags looks spammy, and people won’t click on it.