Groups and teams are similar in that they are a conversation with a group of users, but they do have some differences. A team is a great place to talk about a specific task, project, or topic, while groups are used for more ad-hoc messages, similar to direct messages.
There may be times where you start a group conversation and realize that it’s better suited as a team. In situations like this, instead of creating an entirely new team and losing your conversation history from the group, you can convert that existing group into a team. This allows you to keep your conversation history.
Note: A new group will be created when you add a user to an existing group, and the conversation history will not show.