교재 사이트 HTML Tutorial W3Schools offers free online tutorials, references and exercises in all the major languages of the web. Covering popular subjects like HTML, CSS, JavaScript, Python, SQL, Java, and many, many more. www.w3schools.com 실행 https://www.w3schools.com/html/tryit.asp?filename=tryhtml_attributes_img_src HISTORY 2000 : W3C Recommendation: XHTML 1.0 HTML을 만드는 도구가 XML XML을 가지고 깔끔하게 만들자...