What happens if user device is missing set font?

I have been using a default Arial font in my projects.

I am wondering what would happen if a PC or mobile device doesn't have Arial Font installed.

Will it just default to the device/PC default?

I am sure safeguards are set in for Arial since it is so used so much.

I am curious of what would happen if an uncommon font us used, but not set with a Web Font File?

I was thinking of making an Arial Web Font file and adding it to be safe.

I think Arial is one of the safe fonts that is more or less ubiquitous. If a font is missing the system will pick a different font and use that instead. Construct 3 lets you import web fonts which guarantees a consistent display.

Thank you.