Google Groups
Google Groups is a service from Google that provides discussion groups for people sharing common interests.
There are two versions or types of Pumping Station: One Google Groups. One is public; anyone can join or participate subject to admin activity, and the other, private, group which only members can have access to.
Google Groups for PS1 are sometimes referred to as "the mailing list" or just "the list" or "the email list" or "the messageboard" and could be referred to by other names as well. You can interact with the Google Groups mailing list by getting an email digest of the last 25 posts, or one email digest per day, or one alert per post (highly recommended to create a filter to put all the messages from PS1 in one folder/label) or just by interacting with it through a web interface. Your call. Don't ask to be removed from the list, because you can do that yourself with no assistance at all. Try not to ask to be added to the private group either, until you have tried and tried and failed to do it for yourself - because you can do that without any assistance at all: Google it or see the animated gif link below.
When you ask to join the private Google Group, please TELL US YOUR NAME. We can't always figure out who you are from your email address if it doesn't match your paypal or other email you use with PS1, and even if it does, it's good to know your name to verify your membership.
Yes, apparently you have to have a Google account of one kind or another to use Google Groups. That's between you and Google. We just try to verify that you're a member somehow; if you are, you can get into the private group.
Public list: https://groups.google.com/forum/#!forum/pumping-station-one-public
Members Only, or 'private' Google Group: https://groups.google.com/forum/#!forum/pumping-station-one
Here is an animated GIF that explains how to join the private Google Group:
https://media.giphy.com/media/3oxHQyZOjZ58q34tSE/giphy.gif
Other misc. contact methods listed here just in case you came here for something besides learning about Google Groups at PS1: https://wiki.pumpingstationone.org/Contact_Points