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# Reference manual

## Introduction

```{note}
The SUM shall provide or reference,a quick‐reference card or page for using the software, which summarises frequently used function keys, control sequences, formats, commands, or other aspects of software use.
```

## Help method

```{note}
The SUM shall include the help information about method installation, in terms of the actions to be performed by the user, how to invoke the function, possible errors, how to resolve them and what results to expect.
```

## Screen definitions and operations

```{note}
The SUM shall include the description of the dimensions and capabilities
of the visual display screen.
```

## Commands and operations

```{note}
The SUM shall include a guide to the command language used, operations and functions.
```

## Error messages

```{note}
The SUM shall list all error messages, diagnostic messages, and information messages that can occur while accomplishing any of the user’s functions, including the meaning of each message and the action to be taken after each such message.
```