## 1`` Introduction

Hugs 98 is a functional programming system based on Haskell 98, the de facto standard for non-strict functional programming languages. This manual should give you all the information that you need to start using Hugs. However, it is not a tutorial on either functional programming in general or on Haskell in particular.

The first two sections provide introductory material:

- Section 2: A brief technical summary of the main features of Hugs 98, and the ways that it differs from previous releases.
- Section 3: A short tutorial on the concepts that you need to understand to be able to use Hugs.

The remaining sections provide reference material, including:

- Section 4: A summary of the command line syntax, environment variables, and command line options used by Hugs.
- Section 5: A summary of commands that can be used within the interpreter.
- Section 6: An overview of the Hugs libraries.
- Section 7: A description of Hugs extensions.
- Section 8: Information about other ways of running Hugs programs.
- Section 9: A list of differences between Hugs 98 and standard Haskell.
- Section 10: Pointers to further information.

Whether you are a beginner or a seasoned old-timer, we hope that you will enjoy working with Hugs, and that, if you will pardon the pun, you will use it to embrace functional programming!

### Acknowledgements:

The development of Hugs has benefited considerably from the feedback, suggestions, and bug reports provided by its users. There are too many people to name here, but thanks are due for all of their contributions. A special thank you also to our friends and colleagues at OGI, Yale, and elsewhere, for their input to the current release.