Originally Posted by QuikSsurfer
That's up to you and what size SSD you get.
I'd say it's only necessary for your operating system and whatever applications you plan on using the most (adobe photoshop and aftereffects).
If you get large enough to fit your adobe products on it, they will benefit from it. Stuff like word and excel can do without.
The nice thing is that 1TB drives are so cheap now, you can add them as you need them down the road at a minimal cost.