RAM or random access memory is what your Mac’s processor uses to run all the OS tasks. In other words, if you open up a movie to watch on your Mac, your Mac’s processes uses your RAM to load up that movie, buffer it, open up space to temporarily run your video player and then keep memory allocated to respond to your user clicks like pause, play, record etc. You will find more such tips about why is my mac suddenly slow at this resource link here.
As you can imagine, RAM is very critical to how well your Mac responds. It is particularly important when you have a lot to do on your Mac. For example, if you open up a word document in one window, have about 10 research browser tabs open and also have an audio player open, along with messages, mail, spotlight and Time Machine running the background, your Mac is going to need a lot of RAM to run everything. When RAM is not easily available or already being used by applications that you first started, it will slow everything down after creating a priority queue. Things will begin to work in a first come first serve basis. This is your Mac’s way of telling you that it needs some breathing space.
When your Mac doesn’t respond to your continuous inputs, your best bet would be to back off and give it time to catch up with all your activity.
Another way to work around this problem is to install more RAM. However, RAM is expensive to upgrade. Moreover, not all Macs are upgradable. Or at least there might be a lot of restrictions on how you upgrade your RAM. There are many generations of RAM available and the current ones are DDR4
RAM. But, DDR 4 RAM might not even be supported by your Mac’s motherboard if you bought your Mac before 2012. So, please research before you upgrade your Mac’s RAM.