Nostalgia (noun)

1. A sentimental longing or wistful affection for the past, typically for a period or place with happy personal associations.
2. A longing for something past.

Origin:

From the greek "nostos" meaning "homecoming" and "algos" meaning "pain or ache".

Examples:

1. She felt a wave of nostalgia when she saw the old photo.
2. The song reminded him of his youth, filling him with nostalgia.
3. The movie evoked feelings of nostalgia for a simpler time.
4. He was filled with nostalgia for his childhood home.
5. The smell of freshly baked bread always evokes feelings of nostalgia for her grandmother's kitchen.