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+# Notedeck definitions
+Notedeck introduces many niche and novel concepts.
+It's important to have a shared understanding on what they all mean.
+This document will serve as ground-truth for defining concepts used in Notedeck.
+
+## Account
+a `Keypair` which is saved to disk. 
+The `Keypair` consists of a required public key and an optional secret key.
+
+## Account Manager
+responsible for adding, removing, querying for, and creating new accounts.
+It has access to all accounts saved to disk.
+
+## Column
+A column has access to one account, or None.
+It presents data vertically, in a column.
+There are many different types of columns, each of which present data differently.
+
+The following is an exhaustive list of column types:
+- Home
+- Notifications
+- Direct Messages
+- Global Feed
+- My Profile
+- Relays
+- Followers List
+- Follows List
+- Bookmarks
+- Follower profile
+- Follows profile
+
+## Deck
+A deck presents an ordered collection of columns to the user.
+Columns are presented from left to right in the order of the collection.
+Each column takes up the full vertical height of the app.
+Columns can be resized in the horizontal direction.
+The current deck takes up the whole surface area of the app, besides the side panel.
+The deck has one account associated to it.
+Each column in the deck has the following choice of accessing a keypair: it can use the deck's account, a different, (public only) keypair, or None.
+
+## Deck Configuration
+A deck configuration is all of the deck's settings encoded into a parameterized replaceable event nostr note.
+A deck's configuration is read in order to initialize a deck.
+
+## Account Switching
+The user can switch between accounts.
+
+### Deck switching
+Once the user has selected an account, they can choose which deck they want to present on the screen.
+Each account can have any number (0, 1, 2, ...+) of decks associated with it.