The history of email entails an evolving set of technologies and standards that culminated in the email systems in use today.
However, in the Hemi-Sync application of the technique external light sources are not involved but, rather, the mind is the sole agent of the healing and revitalization.
SNDMSG (Wikipedia) SNDMSG was an early electronic mail program, chiefly notable because it was used to send what is considered the first networked email.
