If you're posting a poll on Mastodon, you can make a "choose one" poll or a "choose one or more" poll.
On the website interface, you can switch types by clicking on the voting buttons when you're posting the poll. When they are circles it will be a "choose one" poll, when they are squares it's "one or more".
The official apps don't (yet) support changing this, some of the third party apps may support it though.
A number of people have replied that this feature isn't obvious enough, and I agree with them.
If you agree too, and if you're comfortable using Github, please give a thumbs up on this thread:
1. Already the assumption that an ordinary user (i.g. my grandma) will associate round boxes with single choise and rectangle boxes with multiple choice is dangerous.
2. Hardly anyone will notice that the boxes are clickable at all.
3. The user can easily change it by accident without noticing.
Looks to me like a schoolbook example for problematic UI design.
@feditips Metatext, tooot and Toot! for iOS all clearly indicate the default single-option poll type and make it pretty obvious how to switch between the two poll types
(I wasn’t aware that the web interface was so weird, as I seldom use it)
@feditips If your instance runs glitchfork, there's just a dropdown instead.
Because whoever came up with the "click on the box to change it" UI probably thought they were clever but it's just needlessly obtuse and confusing.