History TV and Radio advertising?

I'm wondering, how did radio and television advertising come to life?

History TV and Radio advertising?
The Wikipedia page, below, gives July 1, 1941 for the first TV ad in the U.S.A. It was for Bulova watches.





The other page quotes September 22, 1955 for the first TV ad in the U.K. It was for Gibbs SR toothpaste.
Reply:The first advertising-sponsored radio program debuted on February 12, 1924. The show, “The Eveready Hour,” was sponsored by the National Carbon Company. Sponsored programs, which would later give way to spot advertising, provided much of the economic impetus behind the growth of radio and television. Although sponsored programs had virtually disappeared in television and radio by the 1970s, corporate sponsorships became a common source of funding for Web sites in the mid-1990s.