What is Gui4Cli
Gui4Cli is a simple but powerfull language created by D. Keletsekis around the beginning of this century.

It is an interpreted language with very good debugging possibilities.

It has excellent relations with arexx ports, commands and scripts, with CLI commands and scripts.
Describing it as a scripting language is therefor correct, but !!!
- it beats arexx in the ease of writing an usefull script
- it beats Dopus Magellan in the versatility of the gui's you can write and use

who is it written for?
As this website says "time to get creative" : Gui4Cli allows this to be true for everybody, even complete newbees to programming.

And for more serious programming: using Gui4Cli is an excellent way of testing out ideas.
Early prototyping of ideas and gui may help you in many ways. (even if for intellectual properties you want to use a compiled language.)
Bottom up development is natural here; It allows to use the applications you create in an early stage.
Using it for writing the tools you need urgently, for writing tools that have the grip and feel you want: Gui4Cli will empower you.
Maybe Jonh Chandler can convince you http://www.suite101.com/article.cfm/amiga/34520

Simplicity of Gui creation
The creation of a gui for some program (called modestly a 'gui' in Gui4Cli talk) is ultrasimple:
- You can drag & drop the needed gadgets from a 'gui' presenting them all. (or from a 'gui' you created. )
- There is an 'autogui' Gui4Cli program that creates a gui for a CLI command having a template on the fly
See http://gui4cli.com/ami/gui/AutoGui.lha If you don't like the outlay, at least you can modify it to your taste easily
- You can use my GuiCreat.gc http://gui4cli.com/ami/gui/guicreator.lha program that allows you to create gadgetbanks
(vertical, horizontal, matrix layout) in seconds.

and of course any user can move around the gadgets as well.

Gui4Cli therefor deserves its name very well.

Simplicity of writing usefull applications
Gui4Cli is event driven.
Gadgets supposed to react to user action are called "Events"
Event driven (just as javascript, Rebol ) mean you don't have to write loops to make the command sequence attached to a gadget that is made to "happen".
You just have to write a sequence of simple basiclike statements that should be executed.
eg when a button is hit, a checkbox clicked, a listview line selected.

Debugging is easy and fully integrated,
debug mode can be set on & off easily (from any Gui4Cli gui)
step by step mode : idem

Nice guis
Gui4Cli has interesting and simple possibilities to make visually appealing gui's.
You can use icons and images as well as other graphical elements (lines, ellipses, rectangles)

Userfriendlyness
Adding Help information to a gadget is just one line of code:
GadHelp " My help text"
With a minimum of effort your gui will be really user-friendly.

More online info...
The user-manual http://users.online.be/AD/G4Guide/main.html
For scared souls: what installing Gui4Cli does exactly : http://users.online.be/AD/ReadMeNow.htm

But all you need is ...
http://gui4cli.com/ami/progs/gui4cli.lha : the basic archive with installer, the readme above, guide above, tutorial and real life gui's
http://users.online.be/AD/Gui4Cli3.8.7_OS4.lha : the Gui4Cli executable that should replace the one in the Gui4CLI drawer installed.

More guis by diffferent authors
http://gui4cli.com/ami/gcguis.htm

Remark: the manual is in AmigaGuide format. I highly recommend Next reader to make easy searches in such documents.