Frontend Engineerが面接で聞かれそうな質問↓
https://github.com/h5bp/Front-end-Developer-Interview-Questions#general-questions
に答えるDAY1
General Questionsは飛ばして、HTML Questionsの最初の質問から
What does a doctype do?
訳：doctypeってナニ？何してるん？
調べた結果、、、
The <!DOCTYPE> declaration must be the very first thing in your HTML document, before the tag.
The <!DOCTYPE> declaration is not an HTML tag, it is an instruction to the web browser about what version of HTML the page is written in.
In HTML 4.01, the <!DOCTYPE> declaration refers to a DTD, because HTML 4.01 was based on SGML. The DTD specifies the rules for the markup language, so that the browsers render the content correctly.
HTML5 is not based on SGML, and therefore does not require a reference to a DTD.
Tip: Always add the <!DOCTYPE> declaration to your HTML documents, so that the browser knows what type of document to expect.
HTMLファイルの一番最初に書く<!DOCTYPE>宣言は
- HTMLタグではない。
- ブラウザにそのページのHTMLのバージョンを教える。
- HTML4.0１の場合、必要。
- HTML5の場合、不要。