If you are like the vast majority of people these days, there are probably moments where you look at a seemingly random string of letters on the internet, blink, and go, “Huh? What does THAT mean?” Thankfully, most of the time, there is a relatively intuitive explanation for what a piece of internet slang means, although the cultural context surrounding a phrase can be more complicated.

Such is the case for the phrase “HMU.”

What does HMU mean?

HMU is short for “hit me up.” If you are unfamiliar with that expression, don’t worry, it’s easy enough to understand. It essentially means “Give me a call” or “Reach out when you can.” It is essentially one person’s way of telling another to reach out via a call, text, or message in order to further communicate.

There is at least one alternative meaning of HMU, “hook me up,” which means “Please get me something” or “Please get me that thing which you were talking about.” However, “hit me up” is the generally agreed-upon definition.

How long has HMU been around?

Search trends for HMU were non-existent until 2010, indicating that the trend didn’t start to be used until that time period. Trends for this phrase reached their peak around June/July of 2011, and have been relatively stable, albeit lower, since then. There has been no subsequent spike.

How do you use HMU?

HMU is usually meant as a request or as a follow-up. For example:

• “Heading out later today hmu if interested”
• “hmu when you get out of class”

Since it is usually used as a request to one person, or a group of people on a group text, it usually is more common in texting use, rather than social media. However, there are certain moments where one could theoretically tell others on their Facebook or Twitter feed to hit them up if they were interested in doing something. For example:

• “Heading to a concert later tonight, hmu if you want to go!”

Like almost all internet initialisms, this one would have no place in a formal document – particularly given that it is less known than many others. Furthermore, using HMU in all caps is generally frowned upon – it is usually used in all lowercase.

Some have also noted that there is a potentially flirtatious context for HMU, so you should be careful when using it that your intentions are clear.