Hello,
Thanks for your question. Unfortunately, your question is very broad in scope. Generally, when you're looking at a web page, the code on the page is text, but the code will reference either a text element, link, form, or graphic element on the web page. So, when you ask about the appearance of "most non-text items" - it can be just about anything. If you need some basics, please check out Introduction to Web Design for further information.
I hope this helps to answer your question, please let us know if you require any further assistance.
Regards,
Arnel C.