The National Television Systems Committee created the NTSC standard in the United States. NTSC was a format for a gray television signal. With the invention of color television, NTSC extended the format to a color television signal. With the inventions of video players and video game consoles, these devices outputted NTSC signals to televisions. The United States abandoned NTSC broadcasts at 12 June 2009 (by switching to digital broadcasts), but NTSC leaves a legacy of devices, including video game consoles.
NTSC spread from the United States to North America, Central America, some South American countries and a few east Asian countries, including Taiwan, the Philippines, South Korea and Japan. NTSC created a market for NTSC devices in these countries. Other countries had a market for PAL devices.
NTSC uses about 60 vertical blanks per second, so each NTSC video game console must output about 60 frames per second. (Someone might have a more precise number.) So video games for Japanese and US televisions tend to use 60 frames per second.
Contrast PAL, which uses about 50 vertical blanks per second.