Matrix acronyms

A place to share and define all the acronyms used in the matrix.org ecosystem

B

• BACAT: Bottom-Aligned, Clipped-At-Top

C

• CIDER: Contenteditable Input Diff Error Reconcile
• CS (C2S) API: Client-Server Application Programming Interface

D

• DAG: Directed Acyclic Graph

E

• EA: Element Android
• EAX: Element X Android
• E2EE: End-to-end encryption
• EC: Element Call (or Element Cloud, depending on context)
• ED: Element Desktop
• EDU: Ephemeral Data Unit
• EEC: Element Enterprise Cloud
• EES: Element Enterprise Server
• EI: Element iOS
• EIX (or EXI): Element X iOS
• ELS: Event List Summary in matrix-react-sdk
• EW: Element Web
• EX: Element X

F

• FCP: Final Comment Period

H

• HS: Homeserver

I

• ILAG: Improved landing as guest
• IS: Identity Server

M

• MAU: Monthly Active Users
• MELS: Member Event List Summary in matrix-react-sdk
• MSC: Matrix Spec Change
• MXID: Matrix user ID

O

• OTK: One Time Key
• OTWSU: Open Tech Will Save Us

P

• PL: Power Level
• PWLU: Password-less User

R

• RR: Read Receipt
• RM: Read Marker
• ROU: Read Only User

S

• SCT: Spec Core Team
• SFU: Selective Forwarding Unit
• SS (S2S) API: Server-Server Application Programming Interface
• SSSS: Secure Secret Sharing and Storage

T

• 3PID: Third Party Identifier
• TWIM: This Week in Matrix
• TR: Third Room
• TTT: Tempered Transitive Trust (MSC2882)

U

• UIA: User-Interactive Authentication
• UISI: Unknown Inbound Session ID

  Old name to refer to `UTD`
• UTD: Unable to Decrypt