If your Mac runs slow, there are several things that you can do to correct the issue. For a quick check of memory problems First, open Activity Monitor. Select the processes you're experiencing and then press Quit. If the process is taking up excessive memory then you should close it then try it again. You can use the System Memory tab as well to determine if there are there are any processes that run slow on your Mac.
Another reason that could be behind your Mac's slowness is the processor. If you're running a program that is using a lot of CPU, then you need to close it. For this, you need to open the Activity Monitor and press on the "X" button beneath the window's small buttons. It is possible to use Google to look up applications that consume the most CPU power but you aren't sure the apps mac cleaning software are. You should be able to see which apps can slow down your Mac's performance.
Your Mac might also become slower if it has too many programs. The operating system can run slow if there are several programs. It is possible to delete any files that which you do not use, or transfer them to another drive. If you're unsure of why you're experiencing problems Try opening the Activity Monitor and looking at the complete list of processes that are running on your Mac. You should see a few issues - it's an indicator you're using multiple applications in parallel.