>>5063462Serial experiments lain like a lot of art is not completely explained so a couple things I said can be contradicted by some other person who had a different take about it, but in general it's the story of a girl who lives in a world where people are killing themselves but being seen somehow still. As the plot advances it's discovered they did it because they believe their personalities can be transpoted to the wired, the series version of the internet, it's also so full of mythos (mostly 20th century mithos instead of very old mythos), an underground club scene of hackers that are in the know, and the main character navigating trying to discover what happened to a girl she knew and at the same time being absorbed by the wired.
In the girl's case it's the tv instead of the internet but they also can transport their whole selves to another reality.
Since it was one of the first series about the internet, it and Matrix have influenced stories about alternate realities and modern conceptions of self in the current day a lot.
In my humble opinion.