[Is Lack of Heated Bed is a big problem ?]

Hello,

I'm very noob in ultimaker, but i have solid background in 3d design . I printed alot of stuff in 3d using huge printers fed up with some plastic polymer looking like

popcorn I dont remember the name but it was working well. It was during my traning at HP 10 years ago.

I want to buyan Ultimaker , i mainly focus on usablility and durability of medium size parts , i dont know the difference between PLA or ABS

but ABS looks more solid and resistant to water and humidity.

As far i understand the only way to make it stick to the plateform is to use heated bed.

I wonder why this option does not exist in ultimaker and require hacking and adapting .

Can somebody explain me the "real" difference between pla and abs and point me to the right direction .

Regards