"Traditional Wax" is also known as "Strip Wax" where the wax is applied, a paper strip placed on top and then pulled off removing the paper, wax and unwanted hair.  Whereas "Hot Wax" does not use paper strips, the hot wax is applied to the area, allowed to cool slightly and then the wax itself is pulled off removing the unwanted hair.
Typically strip wax is used for larger areas as it is much quicker to apply and remove. It’s almost always used for areas like legs, arms and back. It’s generally better for thicker or less sensitive skin as it grips strongly to both the hair and skin. Hot wax is more suitable for waxing sensitive areas or thicker hair. Which is why it’s often the wax of choice for Bikini, Brazilian and Hollywood waxes, underarm wax and sometimes facial waxing too. As the wax is left on the skin for up to a minute, the heat opens the pores and hair follicles allowing the hair to wax out much more easily. This should theoretically be less painful.