Communication Types: Simplex vs Duplex

There are many different ways of communicating, but what exactly do the terms Simplex and Duplex mean? Here's a brief rundown of what these terms mean.

Simplex Transmission

In Simplex Transmission, data flows only in one direction - from the sending device to the receiving device. Simplex Transmission is used only when the sending device does not require a response from the receiving device. 

Example: A microphone to a loudspeaker

Half-Duplex Communication

Half-duplex communication allows two-way conversations, one-way at a time, such that one person cannot interrupt the other. 

Example: A walkie-talkie

Full-Duplex Communication

Full-duplex describes bi-directional communications all the time. Regular communications between individuals conversing face to face is full-duplex. In other words, you can talk and listen simultaneously. Full-duplex communication allows simultaneous two-way conversations where one person can interrupt the other.

Example: Two people having a conversation.

Exit, Stage Left

If you've ever worked on a stage, read or wrote a script, or have ever watched the Hanna-Barbera cartoon featuring the wanna-be stage actor, Snagglepuss, you've most likely have heard the phrase, "Exit, Stage Left". But what exactly does that term mean?

Here's a quick glossary of stage terms that describe the locations and directions in a theater. Many of these terms actually come from the descriptions of stage actions in a play script.

HOUSE LEFT: the left side of the auditorium from the spectator's viewpoint facing the stage; toward or at the left side of the auditorium from the spectator's viewpoint facing the stage. Also known as Front House Left or Rear House Left.

HOUSE RIGHT: the right side of the auditorium from the spectator's viewpoint facing the stage; toward or at the right side of the auditorium from the spectator's viewpoint facing the stage. Also known as Front House Right or Rear House Right.

STAGE LEFT: the left side of the stage from the actor's viewpoint facing the audience; toward or at the left side of the stage from the actor's viewpoint facing the audience.

STAGE RIGHT: the left side of the stage from the actor's viewpoint facing the audience; toward or at the left side of the stage from the actor's viewpoint facing the audience.

DOWNSTAGE: the part of the stage nearest the audience; toward or at the front part of the stage, nearest the audience. Often used in conjunction with Left or Right: Downstage Left, Downstage Right.

UPSTAGE: the part of the stage farthest from the audience; toward or at the rear part of the stage, farthest from the audience. Often used in conjunction with Left or Right: Upstage Left, Upstage Right.

OFFSTAGE: away from the stage center; toward or at the part of the stage that is out of view of the audience. Often used in conjunction with Left or Right: Offstage Left, Offstage Right.

ONSTAGE: toward the stage center; toward or in the part of the stage that is in view of the audience.

OUT: away from the stage floor and toward the gridiron, referring to vertical movement of scenery, etc.

IN: toward the stage floor, referring to vertical movement of scenery, etc.

Source: Theatre Projects Consultants