Collections are groups of related Resources. Each Collection has its own email address for submissions. Some collections are "shareable", meaning that the list of Resources in the Collection can be viewed at a single URL with a random unguessable URL.
A Collection can optionally have a "whitelist" -- a list of email addresses and domains that may submit messages to your collection address without having to perform the usual followup or "confirmation" step of clicking on a link in the notification email.
Resources that belong to a Collection may have Tags, which provide ad-hoc subgroups within a Collection. Tags may be specified as part of the Collection's email address in this format: collection+tag1+tag2@4thefile.com
Please visit the Collection FAQ for more infoWhen you post a Resource on a public blog or forum, you may not want to reveal certain information such as your email address, full name, etc. The Redact feature allows you to black out selected words or phrases in the Resource (including any forwarded or attached messages). The redact function is available through the Resource edit page (use the edit link in the response email you received when you submitted the Resource), or through your Registered User account.