TV viewing has significantly increased since the 1960s, from 5 hours and 38 minutes per day in 1964 to 7 hours and 39 minutes in 2004. While there were just three major networks in 1964, cable TV was introduced later, and today TV can be viewed online through sites like iPlayer. TV has evolved from black and white to color sets, and from CRT to modern LCD, plasma and LED displays. Brands like Samsung, LG, Sony and Sharp now dominate the TV market. Commercials have been a key part of TV since the 1940s, both sponsoring whole shows and advertising in blocks, with prices varying based on the popularity of the show.