How to get two different size HDDs recognized as one whole

TheCreepySheep

Honorable
Nov 30, 2013
15
0
10,520
Hello!

I have a plan to build a new PC, but I have a problem with storage. Currently I have a 3 TB Seagate drive as my primary storage, and I want too add one more disk. Something like a 2 TB WB Green or similar.
My question is, how to get those two drives recognized as one 5 TB drive (if it is even possible)?
I'm assuming it can't be done with RAID...

Thanks in advance,
TheCreepySheep!