What is Music Theory? - Definition, Terms & History

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  • 0:04 What Is Music Theory?
  • 1:26 Rhythm, Melody, and Harmony
  • 2:20 Other Important Terms
  • 2:51 History of Music Theory
  • 4:08 Lesson Summary
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Lesson Transcript
Instructor: Stephanie Przybylek

Stephanie has taught studio art and art history classes to audiences of all ages. She holds a master's degree in Art History.

Have you ever sung a song? How about tried to write one? In this lesson, learn about music theory, important terms related to it, and the basics of its history.

What Is Music Theory?

Music is all around us. People sing, play instruments, and listen to music on many different devices. But what is music, and how is it made? Consider this basic definition. Music is a way of putting sounds and tones together in an order, combining them to create organized sound.

People have made music for thousands of years, at first with their voices and with simple instruments made from natural materials around them. Musical traditions were likely passed from one generation to another. Eventually, later generations wanted to better understand the ideas behind the sounds. That's how music theory developed.

Music theory is the term for ideas that help us understand music. It explains what music does, and what's going on when we hear it. Music theory puts the ideas and practices of music into a written form, where they can be studied and passed on to others. It's a way to describe and explain music and how it's constructed. So, think of music theory as a means to understand the language of music.

Making music is fundamental to human nature, and you don't need to take music theory classes to be a musician. But understanding music theory can help you better grasp ideas of how music is made and to better read it. It's helpful if you want to compose music of your own. It's also helpful if you want to arrange a work, which means to shift how the music's written to make it appropriate for different kinds of ensembles.

Rhythm, Melody, and Harmony

Music theory involves many concepts and terms. Among the most fundamental are rhythm, melody, and harmony, all of which relate to how music is constructed.

Rhythm is the repeated pattern of movement in sound. It can be fast or slow and is arranged in units of sound called beats. Rhythm makes the music move. Melody is the group of notes or series of pitches that form the tune, or primary voice of music. When you sing a familiar song, you're likely singing the melody. Harmony is multiple lines of notes that complement the melody. They make it more interesting, but they never overpower it.

Harmony is often composed of chords, groups of three or more notes played at the same time. Chords give color to harmony and melody. Melody and harmony are written using notes on a scale. A scale is a range of ascending or descending notes within an octave, or eight-note group.

Other Important Terms

But when writing music, how do you know where to place notes? Music theory also has terms to define how music is written out. Think about a page of sheet music. The individual notes are placed on a staff, drawn out as a series of five lines and four spaces. The location of notes on the staff is signaled by a clef, a symbol that represents where specific note ranges are placed. Two types of clefs include the treble clef and the bass clef. The treble clef has notes that are higher in tone than the bass clef.

History of Music Theory

The first early examples of written music appeared between 800 BCE and the 1st century CE. Around 600 BCE, the Greek mathematician Pythagoras developed the general idea of octave scales and began to look at the science of music. Then, around 521 BCE, the Greeks developed an early type of musical notation.

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