Edward Louis Bernays, born in Vienna on 22 November 1891, is being seen as the 'Father of Public Relations'.
He used advertising campaigns to help major industrial companies to sell their goods. Another word used for this practice is Propaganda. And although propaganda in itself is not new and was 'invented' many hundreds of years earlier, he managed to re-brand it using the insights of his uncle Sigmund Freud. He understood that it was necessary to appeal to the unconscious part of the mind, or as he said it "the engineering of consent".
In 1917 President Woodrow Wilson created the Committee on Public Information (CPI). The CPI was tasked with winning the war at home by firing up a reluctant American population into what George Creel (CPI chairman) called "the white hot mass of patriotism," and spreading the good news about America and its democratic values throughout the world. Bernays was hired as a writer of the war propaganda for the Latin America section.
His work with the CPI had convinced him that if you could sell war by appealing to images and symbols, then you could do the same thing to sell just about anything.
"I decided that if you could use propaganda for war, you could certainly use it for peace,"he told a BBC interviewer in the early 1990s.
A quote from his in 1928 published book "Propaganda":
"The conscious and intelligent manipulation of the organized habits and opinions of the masses is an important element in democratic society. Those who manipulate this unseen mechanism of society constitute an invisible government which is the true ruling power of our country. We are governed, our minds are molded, our tastes formed, and our ideas suggested, largely by men we have never heard of…. It is they who pull the wires that control the public mind."
One of the more notorious changes he made is the introduction of eggs and bacon into the American breakfast. Another one is to increase cigarette sales for women. In a time when it was not common for women to smoke in public, he managed to promote sales using the 'ideal of thinness'. Also using the medical authorities who promoted cigarettes over sweets. The campaign was a smashing success. Part of the promotion was done via the newspapers. You can read in this New York TImes article from Monday 1 April 1929: Group of Girls Puff at Cigarettes as a Gesture of "Freedom".
It is said that he turned down an offer from Nazi party to put them in a better light with the American public. But the Nazis still did use his work to promote themselves in their own country. He wrote the following about it in his autobiography:
"They were using my books as the basis for a destructive campaign against the Jews of Germany. This shocked me, but I knew any human activity can be used for social purposes or misused for antisocial ones." 
In his book from 1928 he also described the process that helped Hitler into place. When you just would replace a few words in the quote you can easily see the picture:
When an Imperial Wizard, sensing what is perhaps hunger for an ideal, offers a picture of a nation all Nordic and nationalistic, the common man of the older American stock, feeling himself elbowed out of his rightful position and prosperity by the newer immigrant stocks, grasps the picture which fits in so neatly with his prejudices, and makes it his own. He buys the sheet and pillow-case costume, and bands with his fellows by the thousand into a huge group powerful enough to swing state elections and to throw a ponderous monkey wrench into a national convention.
The German campaign to 'promote' Hitler did work quite well. They did understand the principles of propaganda and how to use them to create an image and to first gather and later maintain control. One tool of value they used is the in 1933 established Ministry of Propaganda and Public Enlightenment, which was directed by Joseph Goebbels.
In the end it comes down to currency for profit. Promoting a product focusing on the subconscious minds with the only goal to sell the product whether it is necessary or not is at least a dubious goal. More often than not, it is despicable.
Propaganda can also be bought, for example an organization who hires scientist to run a favorable project or experiment. If the scientist would not write such favorable outcome, he can rest assured to lose this organization's benefits.
In a similar fashion you can regards polls or electoral compasses, which favor certain political candidates or parties to influence voters behavior.
The book Propaganda, as written almost 100 years ago, is today as relevant as it was back then.
Read Also: Dr. Hjalmar Schacht
Read Also: Walter Hallstein