What are notes and rests between two bar lines called?

• A. Key signature
• B. Measure
• C. Bar line
• D. Time signature

Answer: (B)

The space between two bar lines is a measure. That segment holds all the notes and rests that fit into one unit of time defined by the time signature. For example, in 4/4 time one measure lasts four beats, so the notes and rests inside that space must add up to four quarter-note beats. The bar lines simply mark the boundaries of each measure, while other terms like the key signature (which shows sharps or flats at the start) and the time signature (which sets how many beats per measure and what gets the beat) describe different aspects of the music.