Although homophonic music was becoming increasingly popular during this time in music history, new forms of polyphonic music were also developing simultaneously. Similar to composers during the Renaissance, composers during this period felt that the art of counterpoint was essential to their artistry. Two extremely strict forms of imitative polyphony, cannons and fugues , were very popular at the time of the Baroque era. To prove their very expertise, composers were sometimes expected to improvise complex fugues at a moment's notice.