Familiarity
One of DITA's strengths is that it takes advantage of existing tags and tools.
DITA and HTML
DITA (top picture) strongly resembles HTML (bottom picture) and works in much the same way, using similar element names as well as a similar structure.
DITA can also be written to render in a browser and uses the OASIS table model.
DITA and Tools
DITA is compatible with CSS and is supported and can be processed with a wide variety of tools both free and paid on almost any operating platform. Some popular DITA tools include the DITA Open Source Toolkit, XMetal, and more.
See DITA Tools A-Z for more tool options.