Nostalgia is a term that describes an idealized and sometimes unreal feeling of longing for moments lived in the past associated with a sentimental desire to return, driven by memories of happy times and old social relationships. The word comes from the Greek nostos (νόστος - "reunion") and ἄλγος (álgos - "pain, suffering"). Nostalgia was already considered a medical condition in the early modern era because it was associated with melancholy, as well as being important in literature as a frequent trope in Romanticism.

Nostalgia is different from saudade, as saudade is directed at a specific target or moment, and can even be overcome by presence or repetition, whereas nostalgia cannot be overcome in the physical field, as it only concerns an idealized vision of the past that each has.

The nostalgic feeling is usually associated with low-frequency sound emissions. We can feel nostalgia in several cases, such as listening to music from the past, exhaling some smell, remembering moments/events lived in the past, etc. And cos doing in actual present people like to scroll...

Here is some generic 80's and 90's nostalgia provoked by images. 

"Brands of a generation"

by AS and not sorted.