If you're using OS X Yosemite and have upgraded your Hard-Drive to an SSD, you would probubly want to use it's full potential and enable TRIM support.
Since OS X 10.10.4, you can enable TRIM support from terminal, without the need to install any 3-rd party applications.
Here is the step-by-step video tutorial on how to do it:
Enable TRIM Support on Mac OS X Yosemite
The exact string that you need to write in Terminal in order to enable TRIM is:
sudo trimforce enable
If you have any questions or need any help about the procedure, please feel free to contact me.