If you're asking that question, it's probably some kind of windfall and you may not have it for long. If you'd made it (investing, working, etc.) then you wouldn't have to ask.
If you have children or grandchildren, open some accounts for them. If they are minors you can open what's called a uniform transfer to minors account with you or someone as the custodian. Most states have them. If your parents had been able to open one when you were born or young and put all of the birthday, Christmas, and graduation money plus a regular small payment, you wouldn't be asking what to do with 80K. You'd consider it some 'weekend' money.
This sounds critical because it is, in a way. Don't ask strangers -- think of your family and progeny to come.
Gad, always the killjoy with the wise advice comes along.....