Pro Tools 101_ An Introduction to Pro Tools 11 ( PDFDrive )

Inputs
The term input refers to an audio signal traveling into an audio hardware
device, such as a mixer or an audio interface.
The inputs available from within the Mix window in the Pro Tools software
vary depending on the Pro Tools system and hardware interface you are
using.
Outputs
The term output refers to an audio signal traveling out of an audio hardware
device, such as a mixer or an audio interface.
The outputs available from within the Mix window in Pro Tools also vary
depending on the Pro Tools system and hardware interface you are using.
Inserts
Most mixers have a feature known as a channel insert. A channel insert is an
audio patch point that allows either a plug-in insert or a hardware signal
processor to be inserted directly into the signal path of the audio channel.
Pro Tools provides 10 insert positions per track, allowing you to process a
track’s signal through multiple software plug-ins and/or external effects
loops in series.
Sends and Returns
The term send refers to a signal path carrying a mix output of one or more
Audio tracks routed for parallel processing. The send may route to an
external receiving device, such as an external reverb or digital delay, or to an
internal processor, such as a software plug-in. Sends can be pre-fader,
meaning the send level is independent of the channel’s fader level, or postfader,
meaning the send level is affected by changes made to the channel’s
fader level. Pro Tools allows you to set sends to pre- or post-fader, as
needed.
When using a send for external processing, the sent signal is received on the
input of an external device, some type of effect or processing is added to the
signal, and then the signal is returned to the original sending device through
an auxiliary input or auxiliary return. When using a send for internal