marketing era
The marketing era, which Kotler says started around the mid-1950s, saw a fundamental shift. Instead of just trying to persuade consumers to buy the products they were making, companies focused on making products that customers wanted to buy. Deciding which products to make and market went from being a case of "filling a hole in the factory" to one of "filling a hole in the market." It was in this era that the field of market research really took off.