Into what sub units are eras divided

In music, eras are often divided into subunits based on different musical styles, historical periods, or significant shifts in the industry. The specific subunits can vary depending on the context and genre, but here are a few common examples:

1. Classical music: Classical music is typically divided into different eras or periods, including the Baroque era (1600-1750), Classical era (1750-1820), Romantic era (roughly 1815-1910), and Modern era (late 19th century to present). Each era has distinctive styles and characteristics.

2. Rock music: Rock music is often categorized into different subunits based on the overall sound, influence, or cultural movement associated with certain time periods. Examples include the 1950s rock and roll era, the British Invasion of the 1960s, the psychedelic rock and folk rock era of the late 1960s, the punk and new wave movements of the late 1970s and early 1980s, and so on.

3. Hip-hop music: Similar to rock music, hip-hop is divided into different eras based on changing styles, trends, and cultural movements. Common subunits include the Old School era (late 1970s to mid-1980s), Golden Age era (late 1980s to early 1990s), Gangsta rap era (mid-1990s to early 2000s), and the various subgenres and movements that have emerged since then.

4. Pop music: Pop music has witnessed several eras with distinct subunits, often based on evolving production techniques, popular trends, and cultural shifts. Some examples include the Bubblegum pop era (1960s-1970s), the Synth-pop and New Romantic era of the 1980s, the Boy Band and Teen Pop era of the late 1990s and early 2000s, and the current era of global pop and electronic dance music.

These are just a few examples, and different genres of music may have their own unique ways of dividing eras into subunits based on artistic, cultural, or historical factors.