Room treatment products include, but are not limited to, Acoustic Panels such as our R3-B Acoustic Wall Panels, acoustical foam products which are mainly used in recording studios and ceiling suspended acoustic baffles which act as a sound diffuser & absorber. Many baffle systems can be found in industrial settings.
Soundproofing products on the other hand are different in the sense that the primary focus is preventing sound wave pass-through. Massive, dense materials and composites such as thick concrete and iron provide good sound wave pass through resistance measured as "TL" = transmission loss (the amount of dB SPL or sound pressure attenuated by an object / material).
In contrast, there are products such as "Hebel" manufactured by CSR Bradford here in Australia. Hebel bricks provide good soundproofing whilst being amazingly light in weight. Hebel is a masonry building product with high fire and acoustic ratings.
There are many methods and techniques used in soundproofing buildings, such as acoustic plaster combined with acoustic insulation (usually rigid glasswool) and brick or steel reinforced concrete. In recording studios, the usual soundproofing method will be "false floors, ceilings and walls with 1 or more layers or rockwool/glasswool in between. This method works quite well when combined with acoustic panels on the outer walls or ceilings to control reverb and slap echo and also provide extra transmission loss. Remember, sound pass-through reduction = soundproofing. Reverberation / noise / echo absorption = acoustic treatment.