There are several varieties of Time Code used across the world and they consist of two variables which I have outlined below:
1. Reference Frequency
The Reference Frequency refers to the AC (alternating current) mains frequency of a particular country or region: 60Hz (North America, parts of South America, Japan, Taiwan, the Philippines, and South Korea) or 50Hz (Australia, most of Western Europe, China, some parts of Africa, India, and elsewhere). This leads into Frame count as the second variable.
2. Frame Count
The Frame Count refers to the number of frames in one second of time code. There are four methods of counting frames with time code: Non-drop frame SMPTE, Drop frame SMPTE, 24 frame SMPTE, and 25 frame SMPTE (EBU).
Timecode and NTSC, PAL and SECAM
Find out here about the relationship to frame rates and frequencies of different countries and regions around the world in this blog post I wrote about NTSC, PAL and SECAM broadcast standards.