What are share groups in salesforce?

<div>Share Group: It allows you to share records owned by high volume community and portal users with internal and external users. It applies across communities or portals and associated with sharing sets.</div>

<div data-md="61"><div aria-level="3" role="heading" data-attrid="wa:/description" data-hveid="CAsQBQ">A group consists of a set of users. A group can contain individual users, other groups, or users in a particular role or territory. It can also contain the users in a particular role or territory plus all the users below that role or territory in the hierarchy.<div><div data-hveid="CAsQBg" data-ved="2ahUKEwiJ-oDY9ZDrAhVNxTgGHSPlCGcQFSgBMAN6BAgLEAY">
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