Both words translate as band, group, faction, or gang according to Wiktionary. Although the words do have a few other meanings as well but I am only interested in this context for now. So, in the context of group or faction, do banda and bando have any difference in meaning or usage? Or is it just a matter of dialectical choice? What would be the preferred word in Mexico?
Banda means a small group of people with common activities (mussical band or gangster band).
Bando means a part in a conflict that is choosen (voluntarily or not) and is translated in english as "faction". Using "Banda" as faction is weird at least in Spanier Spanish.
PD: im spanish
Warning! Banda in spanish also means both sides of an stadium or delimited space. Also, it may mean a rubber band, like in english.
Both have related meanings linked to a group of people.
When you are talking about a music band a gang you use
Tengo una banda de rock.
I have a rock band.
Una banda de ladrones.
A thief gang.
Soundtrack, related to music band.
In México you'll see:
Banda de viento.
Is a music band of northern Mexican music with air instruments.
When the topic is
bando the meaning goes to the faction meaning is easier because it has less meanings:
La opinión pública se dividió en dos bandos.
The public opinion was divided into two groups.
Both words have other meaning but they are etymologically apart.
The use of these two words is basically the same in the entire Spanish speaking world but I found that
bando in Spain means also an edict, to publish a law or something official said by the government.
In Mexico when you say:
Do you like banda?
You're asking to a person if likes the music of banda —La música de banda—. This is a Mexican music genre very popular among the northern states and now very spread all over the country.
La banda like this as a noun refers specifically to this genre.
No, no me gusta la banda.
No, I don't like banda.