Yashar Ali, a contributor for New York Magazine and HuffPost, created a easy to understand resource on unclaimed property and how to receive what you may be owed.
What is unclaimed property? According to unclaimed.org, unclaimed property "refers to property or accounts within financial institutions or companies - in which there has been no activity generated (or contact with the owner) regarding the property for one year or a longer period."
There are multiple types of unclaimed property that include checking and savings accounts, contents of safe deposit boxes, refunds, stocks, and a multitude of other options outlined in the article linked above.
For an easy to follow resource on how to claim this money, check out his Twitter thread below.