I want to admit that there are two main reasons for such a slow work of your Mac. Firstly, it can happen because of old hardware that can no longer cope with modern applications and works at its edge already. Secondly, overloading Mac OS X with different apps and unnecessary files causes such troubles.
You know, something strange happens with my Mac apps sometimes. They start to lag and in some cases stop working at all. This is what happened to uTorrent once. It is one of my most frequently used applications. It has refused to open. After launching, the app’s icon simply jumped on the launchpad endlessly... I decided to uninstall uTorrent from my Mac and download it again, as I often do. So, now I'll tell how I removed uTorrent from my Mac.
Apple users have a privilege of picking up a conversation from iMessage that they started on iPhone, right on MacBook, or vice versa.