When should I use 'band' and when 'act', particularly in the musical context?
Checking the Google Ngram service, I see that rock bands is more common than rock acts. Instead hip-hop acts is more common of hip-hop bands.
Update
I add some more context from Wikipedia
Chicago house music acts from the early to mid-1980s found success on the US dance charts on various Chicago independent record labels that were more open to sign local house music artists. These same acts also experienced some success in the United Kingdom, garnering hits in that country. Due to this success, by the late 1980s, Chicago house music acts suddenly found themselves being offered major label deals. [...] UK acts such as The Beatmasters, Krush, [...] opened the doors to house music success on the UK charts.
Is there a reason why they do not say artists or bands for acts? Are they just synonymous? It does not seem to me here that "act" here is used to mean a specific performance, like @Hot Licks suggest.
I am interested to everyday English or formal English as it might be used by Wikipedia and not some technical jargon used by music specialists (to answer @jsw29)