modern history including the 16th century and 17th century can be connected. the 18th century including the early 18th century, early mid 18th century, mid 18th century, late mid 18th century, and late 18th century can be connected. the 19th century including the early 19th century, early mid 19th century, mid 19th century, late mid 19th century, and late 19th century can be connected.
the 20th century including the early 20th century, early mid 20th century, mid 20th century, late mid 20th century, and late 20th century can be connected. the early 21st century including the early 2000s, late 2000s, early 2010s, and late 2010s can be connected. the future can 