system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: The difference betweens the forms of classical music, like fugue, minuet, canon, opera, prelude, sonata, etc.

Title, and thanks.
gpt
To some extent, this is like asking what's the difference between rap, gangsta rap, DJ, country, Electric Slide, drum solo.  Some of the terms can be compared, but some cannot.

An opera is a dramatic work that features mostly singing  Like a musical or a play, but the performers sing through most, or all, of it.  It also means the name of the group that performs that kind of work.  This is a big-picture term.  Some comparables might be "ballet" (classical work performed while folks dance)  or "symphony" (classical work performed by a larger ensemble... it sometimes has a regular form, but doesn't have to) or even "string quartet." (classical work performed by four string musicians)

"Sontata" is a type of work or a type of form, usually characterized by an A-B-A form, meaning there's a statement of a theme, there's a contrasting part, and then there's a "recapitulation" of the theme.  It could be a "sonata for strings," or a "piano sonata," or it could be a smaller part of a larger work (many movements of a symphony are written in sonata form).  Comparables to this are things like a Rondo/Rondo form (ABACABA).

A minuet was a dance -- like the Electric Slide -- popular in the 1700s, in 3/4 time.  It's a little bit slower and often more formal than some of the later fast 3/4 dances.  Comparables might be things like a gigue (jig-- in a fast 6/8) or a march (2/4 or 2/2), or polonaise (another 3/4 dance but from a different time and different place than the minuet), waltz (a faster 3/4 dance, popularized later).

A "canon" is a round, like "three blind mice," where mutiple people sing or play the same notes, but at offset times.  There are variations on this, and you can have an "accompanied canon" where not all performers play a part in the canon.  (The famous "Pachelbel Canon in D" isn't really a canon.)  Similarly a "Fugue" employs the same device, but each part usually starts on a different pitch.  While there can be entire pieces written as fugues (bach liked to do this) or canons, most often this is a type of compositional strategy-- a section in a piece--to add contrast or interest.