# Overview

## Task

NC machining can be commanded by a variety of different interfaces and functions:

1. Automatic program: Start a previously created program
2. Manual block: Specify an NC command possibly consisting of several lines
3. Streaming: Specify sequential subcommands online (not described here)
4. PLC: commanding via PLC interface in compliance with PLCopen

## Characteristics

Many user commands or other geometry profiles are only defined online, i.e. when the workpiece is already being machined. The programming environment and the PLC display user actions interactively to send commands to the controllers. Among other things, this affects:

- creating the geometry
- user commands and forward/backward motion
- aborting machining with subsequent resumption

Due to the incremental online specification of program parts, users can define and influence the process in real time.

## Parametrisation

Parameterisation is executed using P-CHAN-00158. This and other commands are described in detail in the chapter Parameters.