Are the technologies in Serial Experiments Lain based on real world technologies? There's quite a few different types of technology (and computers) referenced in the world of Serial Experiments Lain, while some of them are easily matched, some of them aren't. In addition, some of the technologies weren't available at time of production (for example: speech recognition).
Familiar technologies:



The Wired

The Wired is similar to The Internet and runs on IPv4.

Tachibana Industries

Based on their naming schemes and designs, they're most likely a reference to Apple Inc.

Alice's Navi:

Alice's Navi looks like the bubble iMac G3:




Lain's original Navi

Lain's original Navi is based off the 20th Anniversary Macintosh:




C Language

The Navi systems run C:



Common Lisp Language:

The Navi systems also run Common Lisp (A dialect of Lisp):



MIPS-ASM

During one of the scenes where Lain is on her Navi, Assembly code identified to be MIPS-ASM flashes across the screen.

Copland OS:

The OS that the Navis run, Copland OS is based on a failed Apple project from two years prior.

PHANTOMa

PHANTOMa is similar to dungeon games like Might and Magic and Dungeon Master.




HandiNAVI

The HandiNAVI is similar to the Apple Newton line.




Protocol Seven

Protocol Seven is Internet Protocol version 7 (drafted in 1993) an RFC that was never implemented in favour of Internet Protocol version 6, whose RFC was drafted in December 1998, after the series had finished.



Unfamiliar:

Psyche chip

In Layer 02, Lain gets a chip that lets her interact with the Wired without standard input devices. This is similar to the concept of Virtual Reality, yet is beyond today's technology.





Unavailable at time of production:

CU Mail

In Layer 11, Alice is in a videocall with Juri. This is similar to today's videocalling services like Skype and Google Hangouts.

Navi's speech recognition:

Lain is seen controlling her Navi via speech recognition. This is similar to today's Cortana and Siri.