The word arpeggio comes from the Italian word arpeggiare, which means to play on a harp.
An arpeggio consists of a chord notes played one after the other, not at the same time how are the block chords notes played. Even though the notes of an arpeggio are not played or sung all together at the same time, listeners hear the sequence of notes as forming a chord.
Any two or more notes sounded simultaneous are known as a chord. The most frequently used chords are triads, so-called because they consist of three distinct notes stacked vertically in thirds. The lowest-pitched tone being the root, then comes the third, and the fifth, which is the highest.
You can find bellow the illustrations of all Major Triads and also information about triads types and triads inversions.