MacBook – Which types of SSD are compatible with mac book pro mid-2012 (not retina)

As long as you can confirm the laptop is indeed from mid-2012 (later models have the memory soldered in), then these specs should work for you with either a 13" or 15" laptop (Apple started soldering memory in 17" laptops after 2011):

• 204-pin
• PC3-12800 DDr3 1600 MHz type RAM

(Found at http://support.apple.com/kb/HT1270)

As far as hard drives go, I'd personally recommend a Crucial SSD, but yes, any solid state drive will work.

Hope this helps!

Yes, you can upgrade the drive in your MacBook Pro 13 Mid 2012 to an SSD. Here is a detailed guide from iFixit specifically on hard drive replacement.

And here are more tutorials from Other World Computing on how to handle various upgrades such as memory, hard drive, battery replacement, etc…