mediumwhat am-i

I can bring tears to your eyes; resurrect the dead, make you smile, and reverse time. I form in an instant but I last a lifetime. What am I?
Common Wrong Answers
“A photograph”
While a photograph can evoke memories and emotions, it is a physical object and does not encapsulate the concept of a memory itself, which is intangible.
“A dream”
Dreams can bring emotions and sometimes reflect memories, but they are fleeting and often forgotten, unlike memories that can last a lifetime.
“A song”
A song can evoke memories and emotions, but it is not the same as a memory itself; it is merely a medium through which memories may be accessed.