Level 1 - Pitch

Contour describes the shape of a melody. A contour line can be used to describe the shape of a melody:

Melody - is a series of notes that make up the main idea or phrases of a piece of music.

The vocalist in 'Be My Guest' is singing the melody, whilst the orchestra is providing the accompaniment.

In this example the orchestra plays the melody in the beginning and then is repeated by various sections of the orchestra.

Accompaniment - is music that supports the melody. It's role is to 'back-up'  the main melody.

In the following piano piece the left hand role is to provide the accompaniment to the right hand that has the melody.

Here is another example of a rock song where the singer has the melody and the other instruments provide the accompaniment.

Scales - Ascending and Descending

Scales are a series of 8 notes that determine the key that a piece of music is in. When a composer is writing a melody in the key of C major for example, they will use the notes from the C major scale to develop their melody.

Chords 

A chord is a series of notes played together. A major chord uses the notes 1, 3 & 5 from the major scale. For example a C major chord uses the notes C, E and G.

Most popular songs use three or four different chords. These chords are usually chords 1(i), 4 (iv) and 5(v). If the song is in the key of C major, chord 1 is C, chord 4 is F and chord 5 is G.

Listen to the chords 1, 4 and 5 being played on piano.

Here is an example of songs who use four chords.

Riff

A riff is a series of chords or a short melody that is repeated at various stages in a rock song. It is usually played by the guitar.

Here is some famous examples of rock riffs.