THE MOST IMPORTANT HTML TAGS FOR NOW

Above head section

<!DOCTYPE HTML>

<html></html>

Head section

<head><head>

<meta/>

<title></title>

<style></style>

<link/>

<script></script>

Body section

<h1></h1>,<h2></h2>,<h3></h3>,<h4></h4>,<h5></h5>

<a></a>

<br/>

<img/>

<div></div>

<link/>

<span></span>

<script></script>

<i></i>

<label></label>

<input>

<ol></ol>

<ul></ul>

<li></li>

<p></p>

<strong></strong>

<form></form>

<nav></nav>

<header></header>

<main></main>

<article></article>

<section></section>

<figure></figure>

<figcaption></figcaption>

<footer></footer>

<fieldset></fieldset>

<legend></legend>

<select></select>

<option></option>

<button></button>

<form></form>

<textarea></textarea>

THE MOST IMPORTANT HTML ATTRIBUTES FOR NOW

<a class="#"></a>

A space-separated list of the classes of the element. Classes allows CSS and JavaScript to select and access specific elements via the class selectors or functions like the method Document.getElementsByClassName().

<a src="#"></a>

The image URL. 

This attribute specifies the URI of an external script; this can be used as an alternative to embedding a script directly within a document.

<a rel="#" ></a>

This attribute names a relationship of the linked document to the current document. The attribute must be a space-separated list of the link types values.

<a href="#"></a>

Contains a URL or a URL fragment that the hyperlink points to.

This attribute specifies the URL of the linked resource. A URL can be absolute or relative.

<a type="#"></a>

This attribute is used to define the type of the content linked to. The value of the attribute should be a MIME type such as text/html, text/css, and so on. The common use of this attribute is to define the type of stylesheet being referenced (such as text/css), but given that CSS is the only stylesheet language used on the web, not only is it possible to omit the type attribute, but is actually now recommended practice. It is also used on rel="preload" link types, to make sure the browser only downloads file types that it supports.

<a id="#"></a>

Defines a unique identifier (ID) which must be unique in the whole document. Its purpose is to identify the element when linking (using a fragment identifier), scripting, or styling (with CSS).

<a style="#"></a>

Contains CSS styling declarations to be applied to the element. Note that it is recommended for styles to be defined in a separate file or files. This attribute and the <style> element have mainly the purpose of allowing for quick styling, for example for testing purposes.

<a title="#"></a>

Contains a text representing advisory information related to the element it belongs to. Such information can typically, but not necessarily, be presented to the user as a tooltip.

<a target="#"></a>

Specifies where to display the linked URL. It is a name of, or keyword for, a browsing context: a tab, window, or <iframe>. The following keywords have special meanings:

_self: Load the URL into the same browsing context as the current one. This is the default behavior.
_blank: Load the URL into a new browsing context. This is usually a tab, but users can configure browsers to use new windows instead.
_parent: Load the URL into the parent browsing context of the current one. If there is no parent, this behaves the same way as _self.
_top: Load the URL into the top-level browsing context (that is, the "highest" browsing context that is an ancestor of the current one, and has no parent). If there is no parent, this behaves the same way as _self.

<a lang="#"></a>

Helps define the language of an element: the language that non-editable elements are in, or the language that editable elements should be written in by the user.

<a charset="#"></a>

This attribute declares the page's character encoding. It must contain a standard IANA MIME name for character encodings. Although the standard doesn't request a specific encoding, it suggests:

Authors are encouraged to use UTF-8.

<a name="#"></a>

This attribute defines the name of a piece of document-level metadata. It should not be set if one of the attributes itemprop, http-equiv or charset is also set.

<a content="#"></a>

This attribute contains the value for the http-equiv or name attribute, depending on which is used.

<a http-equiv="#"></a>

Too compicated, just use it: X-UA-Compatible

<a alt="#"></a>

*Knowledge from Visual Studio Code