Key Concepts. 1  The electrons on the outermost energy level of the atom are called valence electrons. 2  The valence electrons are involved in bonding one atom to another. 3  The attraction of each atomâs nucleus for the valence electrons of the other atom pulls the atoms together.
NTSC is the format used in the United States and Canada. NTSC stands for National Television Standard Committee which established the American TV broadcast TV standard as a 525 line broadcast. The NTSC system has higher frame rate (60 Hz) which reduces visible flicker and picture noise.
It is so named because of the PAL television standard traditionally used in those regions, as opposed to the NTSC standard traditionally used in Japan and nearly all of North America. Most video games designated as part of the region will not play on NTSC-U/C or NTSC-J region consoles because of regional lockout.