A few centuries ago, dating was sometimes described as a "courtship ritual where young women entertained gentleman callers, usually in the home, under the watchful eye of a chaperone," but increasingly, in many Western countries, it became a self-initiated activity with two young people going out as a couple in public together.
Still, dating varies considerably by nation, custom, religious upbringing, technology, and social class, and important exceptions with regards to individual freedoms remain as many countries today still practice arranged marriages, request dowries, and forbid same-sex pairings.
It generally happened in that portion of a person's life before the age of marriage, enabled dates to be arranged without face-to-face contact.
Cars extended the range of dating as well as enabled back-seat sexual exploration.
Information about human sexuality grew, and with it an acceptance of all types of sexual orientations is becoming more common.