UML might be what you're looking for. http://en.wikipedia.org/wiki/Unified_Modeling_Language

you can use GMF in eclipse. Check the following link. You can do it with eclipse juno. I have made once. Just follow the picture step by step. When you know the procedure you can design your own diagram.

http://gmfsamples.tuxfamily.org/wiki/doku.php?id=gmf_tutorial1#comment_2edc571936e5c0a7d1f0e2524177ee19

Check this video.

https://www.youtube.com/watch?v=jhQctnSryTE

Papyrus supports UML, SysML, is highly configurable, free (Epl licence), in active development, and has all the things that you asked for. Also, Papyrus supports domain-specific modelling language engineering using the standard UML profiles extension mechanism, tables (based on the popular Nattable) and even a wide range of advanced extra plugins supporting many and diverse subjects such as model simulation, robots modelling and real-time embedded systems.

Best!!

http://www.eclipse.org/papyrus/

In case you want to go on with the advice of Christopher and draw UML diagrams, you should have a look at the graph drawing tool yEd. It supports all kinds of vector formats, has an intuitive way of snapping UML elements to positions related to neighboring elements. It even supports exporting data into the EMF file format, which is suitable to be imported into MS Word, creating nice vector graphics once exported from MS Word to PDF. Obviously, it also supports common formats suitable for TeX processing as eps, pdf, ... 

See:

http://www.yworks.com/en/products/yfiles/yed/

It is for free. 

I also use yEd for drawing system diagrams, it's an excellent tool.

If you really, really want to do this, be prepared to spend a tremendous of time and effort, person-years even. It's one thing to create a toy-tool for  yourself, its completely another to create a viable, marketable product.

UML offers a big range of features for visualisation of specifications and designs. Most probably you will need to stop at a certain level of detail, once you will want to include the users in the design, let's say don't go beyond a use case diagram. 

See: http://en.wikipedia.org/wiki/Use_Case_Diagram

Use case diagrams can already get quite complex using everything what the UML standard offers. The problem does not only reside on the level of the (unknown / known / understandable) notation in my eyes, also consider the concepts which need to be understood. For instance, once you will introduce class diagrams, object diagrams or similar, any further conversation needs to build on a common understanding of object orientation (in case you will use that concept / a corresponding language). Seeing some of our students having serious problems in understanding object orientation, I would rather advise to avoid such level of detail in discussions with non-programmers. 

Often the best is to use language that is close to what customer already knows and uses. That is often also called as a domain-specific modeling language. In your case it could model data, accounts, operations, and possibly also UI parts with dialogs, buttons, fields etc.These are concepts of the language itself that your users would apply.

In other words, they would not model classes, visibilities or other UML stuff mapping to implementation as they hardly want to learn all that part. For cases of this appraoch, please see e.g. http://www.dsmforum.org/cases.html

Modeling and using domain specific languages is a good idea. Thus, the users, being non-programmers can stay within their terminology, as outlined by Juha-Pekka.

You could also find talks on that topic on youtube. For instance, see this talk held a Google by Peter Friese:

https://www.youtube.com/watch?v=bhdGNTm4PzI

This might provide you with a more precise idea of what Juha-Pekka proposes. 

"Visual programming" and the related "Model Driven Architecture" (MDA) is an old research topic.  There are also many commercial products that do this.  

There are also component libraries that can help you build diagramming tools. Example: http://www.nwoods.com/products/godiagram/

Another interesting implementation approach you might consider duplicating has been implemented by the open source PlantUML project. Their tool generates the full suite of UML diagrams from a very simple mark up textual language that is quite easy to learn (even for a novice). The UML markup is parsed and converted to the GraphViz dot language (also free and open source). The GraphViz  engine then generates diagrams using several different automated layout algorithms.  The PlantUML markup allows you to give hints to the GraphViz engine to improve the diagram layout.

My thinking is that you would design your own diagram based language and then encode it as a simple markup that you similarly parse and convert into GraphViz  dot.

For smaller UML projects I personally find PlantUML's textual diagramming very quick to work with (faster than traditional UI based UML tools). I use a free plugin for IntelliJ IDEA/Webstorm based on PlantUML. It displays the resulting diagram as you type the text.  There are also similar standalone PlantUML UI tools.

Refs:

• http://plantuml.sourceforge.net/ 
• http://graphviz.org/
• https://plugins.jetbrains.com/plugin/7017
• http://sourceforge.net/projects/plantumlqeditor/  
• http://www.planttext.com - Online UML editor - Give it a try!

It depends on the target language that the software will be written in and the size and scale of the target software. I don’t think you will have a visual software design tool and will produce a 100% usable software straight from design without some form of modification to add in the details and to provide the core functionalities and logic of the intended software.

On the Java platform, there are a combination of tools that you can use that will provide you with about 60-70 % of your target software capabilities. These tools are used for some of the specific parts of the software development process e.g. design, UI, database and business logic.

For example, UML for design, as the others have mentioned, UML is one of these tools and can provide a code generation for your design however, most of the code generated are design or placeholder code constructs and will need a developer to supply the details. Hibernate for automatic database creation and relationship mapping based on your object model, Spring-MVC to help automate some parts of your software development etc. WYSIWYG editors for your front-end design and HTML automatic code generation (assuming you are building a web application) etc. Java annotations and open source frameworks to help with some of your business logic etc.

You have to use a combination of tools to achieve the desired outcome.

Hello Buddika,

we are building an open-source tool named Kroki that allows fast prototyping of business applications  even for non-programmers. All models developed by Kroki are immediately executable.  Its site is here: http://www.kroki-mde.net

Please, do not hesitate to ask if you have any further questions.

If you need to customize or define your own design notations, I would suggest you to use Meta-CASE, for example Generic Modeling Environment (GME) http://www.isis.vanderbilt.edu/projects/gme. I had an experience in using GME in my research project.

(Note: I work for this company): If you are in the university you may consider Academic License of MetaEdit+ (~100 universities using, see functionality, terms etc at: http://www.metacase.com/store/academic_license.html).