The simplest and most obvious scale is the C major scale, which consists of all the white keys {C, D, E, F, G, A, B}. As it turns out, all traditional scales in Western music are variants on this scale. Incidentally, the "complimentary" scale to that one (consisting of all the black keys {Db, Eb, Gb, Ab, Bb}) is commonly used in Eastern music, and is known as the pentatonic scale, due to its having 5 different notes. Really, any scale with 5 different notes could be called a pentatonic scale, but if someone just says "the pentatonic scale" without further specificity, it's generally assumed that they're referring to the one consisting of all the black keys. The C major scale and its many variants are known as heptatonic scales, but afaik there is no one heptatonic scale which is known simply as "the heptatonic scale" and the word heptatonic isn't actually used very much (Chrome's spellchecker doesn't even recognize it, but it does recognize pentatonic).