Why is it difficult to render math(s) in a browser?

OK. I am new to MathML so forgive my ignorance.

But, I have heard it said that math(s) is difficult to render in a browser.

Why so???

MS Equation Editor has no difficulty rendering math(s) in a word doc so why
not a similar setup in a browser. In fact the same setup.

What's wrong with that?

James Butler.

Research Assistant, Corporate Technology Group.

Reuters Ltd.
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