This information is only relevant for Admins managing a Playground Private Exchange.
There are certain types that are important to Playground as it drives some additional functionality (via Play Actions) on the Platform. Playground has two default types (Salesforce & Package) which has their own set of actions & lifecycle.
With Salesforce type plays, you can access robust features like creating / manageing plays direclt from any Salesforce org & One-Click hassle free deployments.
Package type plays allows you to store & manage all your Managed / Unmanaged Salesforce packages along with your other Salesforce plays. It also gives ability to install them directly into any of your Salesforce orgs.
Playground doesn't restrict users to add only Salesforce plays. Admins can configure any Play type (Be it like Python, NodeJS or Java) for the users which help them to categorize all their plays accordingly. All platform capabilities & collaboration works as it is.