I recently installed the Samsung 840 Pro in my MacBook Pro. There is a disk that comes with the SSD and includes the Samsung Magician software for the SSD to keep the firmware of the SSD up to date. It doesn't look like it's compatible with Mac. Is this software necessary?
Samsung Magician Software is only compatible with Windows. You don't need it in Mac because it's not compatible, but it would be useful to upgrade the SSD firmware easily.
If you want to upgrade the SSD firmware, you have to download the ISO, burn it into a DVD or USB drive and start up your Mac from it. See the SSD firmware updates for Macs > http://www.samsung.com/global/business/semiconductor/samsungssd/downloads.html