LaTeX is a typesetting system that gives you full control over how everything in your document is rendered. The problem is its really steep learning curve. One option is to use a basic text editor and learn all the markup you need for your document. The other option is to use an application that wraps the markup to some degree. LyX does this very nicely. While a fully WYSIWYG editor for LaTeX doesn’t make sense (since your doc isn’t fully rendered until sent to an output device), LyX does provide a pseudo-WYSIWYG interface where you can see how different regions will be rendered.
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