In a benign scenario that doesn’t involve malware, there are basically two ways to address the problem. You might want to start with assessing your running applications to identify the ones that are consuming RAM redundantly. Go to Utilities, select the Activity Monitor, click on the Memory tab, and take a look at the overly “hungry” programs. If you discover an app that you hardly ever use but it’s still devouring a good deal of memory, consider uninstalling it. Another method to sort the issue is to install extra memory. However, you should do your homework first to find out if your Mac model supports RAM upgrades or not. Here’s a quick tip: if you own a MacBook Air, it’s a no-go. Some MacBook Pro laptops can be upgraded, but this only holds true for mid-2012 models and earlier. There are some additional restrictions, though. Don’t fail to look up your computer’s specifications on the official Apple resources – there could be mentions of the maximum allowed amount. If you are up to going this route, be sure to install an equal amount of memory in each slot. In the event you are dealing with malicious code that fakes the low memory problem, the only way to stop the alerts is to get rid of the infection. Since this malware usually manifests itself at the system-wide and web browser levels, the cleanup should address both. See the tutorial above for detailed removal steps.