diff --git a/packages/rocketchat-markdown/parser/original/code.js b/packages/rocketchat-markdown/parser/original/code.js
index b7445b5c819..4f16d8c320b 100644
--- a/packages/rocketchat-markdown/parser/original/code.js
+++ b/packages/rocketchat-markdown/parser/original/code.js
@@ -7,6 +7,7 @@ import { _ } from 'meteor/underscore';
 import hljs from 'highlight.js';
 
 const inlineCode = (message) => {
+	// Support `text`
 	message.html = message.html.replace(/(^|&gt;|[ >_*~])\`([^`\r\n]+)\`([<_*~]|\B|\b|$)/gm, (match, p1, p2, p3) => {
 		const token = `=&=${Random.id()}=&=`;
 		message.tokens.push({
@@ -20,8 +21,10 @@ const inlineCode = (message) => {
 };
 
 const blockCode = (message) => {
+	// Count occurencies of ```
 	const count = (message.html.match(/```/g) || []).length;
 
+	// Check if we need to add a final ```
 	if (!count) {
 		return message;
 	}
@@ -34,11 +37,13 @@ const blockCode = (message) => {
 	// Separate text in code blocks and non code blocks
 	let msgParts = message.html.replace(/<br>/gm, '\n').split(/^.*(```(?:[a-zA-Z]+)?(?:(?:.|\n)*?)```)(.*\n?)$/gm);
 	msgParts = msgParts.map((part) => {
+		// Verify if this part is code
 		const codeMatch = part.match(/^```(\w*[\n\ ]?)([\s\S]*?)```+?$/);
 		if (null == codeMatch) {
 			return part;
 		}
 
+		// Process highlight if this part is code
 		const singleLine = codeMatch[0].indexOf('\n') === -1;
 		let code = null, lang = null;
 		if (singleLine) {
@@ -67,6 +72,7 @@ const blockCode = (message) => {
 		return token;
 	});
 
+	// Re-mount message
 	message.html = msgParts.join('');
 
 	return message;
diff --git a/packages/rocketchat-markdown/parser/original/original.js b/packages/rocketchat-markdown/parser/original/original.js
index 7aaa1e5f1fa..f6fdba3fc15 100644
--- a/packages/rocketchat-markdown/parser/original/original.js
+++ b/packages/rocketchat-markdown/parser/original/original.js
@@ -20,34 +20,65 @@ export const original = (message) => {
 	}
 
 	const schemes = RocketChat.settings.get('Markdown_SupportSchemesForLink').split(',').join('|');
+
+	// Support ![alt text](http://image url)
 	msg = msg.replace(new RegExp(`!\\[([^\\]]+)\\]\\(((?:${schemes}):\\/\\/[^\\)]+)\\)`, 'gm'), (match, title, url) => {
 		const target = url.indexOf(Meteor.absoluteUrl()) === 0 ? '' : '_blank';
 		return `<a href="${url}" title="${title}" target="${target}"><div class="inline-image" style="background-image: url(${url})"></div></a>`;
 	});
+
+	// Support [Text](http://link)
 	msg = msg.replace(new RegExp(`\\[([^\\]]+)\\]\\(((?:${schemes}):\\/\\/[^\\)]+)\\)`, 'gm'), (match, title, url) => {
 		const target = url.indexOf(Meteor.absoluteUrl()) === 0 ? '' : '_blank';
 		return `<a href="${url}" target="${target}">${title}</a>`;
 	});
+
+	// Support <http://link|Text>
 	msg = msg.replace(new RegExp(`(?:<|&lt;)((?:${schemes}):\\/\\/[^\\|]+)\\|(.+?)(?=>|&gt;)(?:>|&gt;)`, 'gm'), (match, url, title) => {
 		const target = url.indexOf(Meteor.absoluteUrl()) === 0 ? '' : '_blank';
 		return `<a href="${url}" target="${target}">${title}</a>`;
 	});
 
 	if (RocketChat.settings.get('Markdown_Headers')) {
+		// Support # Text for h1
 		msg = msg.replace(/(?:^|\n)# (([\S\w\d-_\/\*\.,\\][ \u00a0\u1680\u180e\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff]?)+)\n?/gm, '<h1>$1</h1>');
+
+		// Support # Text for h2
 		msg = msg.replace(/(?:^|\n)## (([\S\w\d-_\/\*\.,\\][ \u00a0\u1680\u180e\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff]?)+)\n?/gm, '<h2>$1</h2>');
+
+		// Support # Text for h3
 		msg = msg.replace(/(?:^|\n)### (([\S\w\d-_\/\*\.,\\][ \u00a0\u1680\u180e\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff]?)+)\n?/gm, '<h3>$1</h3>');
+
+		// Support # Text for h4
 		msg = msg.replace(/(?:^|\n)#### (([\S\w\d-_\/\*\.,\\][ \u00a0\u1680\u180e\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff]?)+)\n?/gm, '<h4>$1</h4>');
 	}
 
+	// Support *text* to make bold
 	msg = msg.replace(/(^|&gt;|[ >_~`])\*{1,2}([^\*\r\n]+)\*{1,2}([<_~`]|\B|\b|$)/gm, '$1<span class="copyonly">*</span><strong>$2</strong><span class="copyonly">*</span>$3');
+
+	// Support _text_ to make italics
 	msg = msg.replace(/(^|&gt;|[ >*~`])\_([^\_\r\n]+)\_([<*~`]|\B|\b|$)/gm, '$1<span class="copyonly">_</span><em>$2</em><span class="copyonly">_</span>$3');
+
+	// Support ~text~ to strike through text
 	msg = msg.replace(/(^|&gt;|[ >_*`])\~{1,2}([^~\r\n]+)\~{1,2}([<_*`]|\B|\b|$)/gm, '$1<span class="copyonly">~</span><strike>$2</strike><span class="copyonly">~</span>$3');
+
+	// Support for block quote
+	// >>>
+	// Text
+	// <<<
 	msg = msg.replace(/(?:&gt;){3}\n+([\s\S]*?)\n+(?:&lt;){3}/g, '<blockquote class="background-transparent-darker-before"><span class="copyonly">&gt;&gt;&gt;</span>$1<span class="copyonly">&lt;&lt;&lt;</span></blockquote>');
+
+	// Support >Text for quote
 	msg = msg.replace(/^&gt;(.*)$/gm, '<blockquote class="background-transparent-darker-before"><span class="copyonly">&gt;</span>$1</blockquote>');
+
+	// Remove white-space around blockquote (prevent <br>). Because blockquote is block element.
 	msg = msg.replace(/\s*<blockquote class="background-transparent-darker-before">/gm, '<blockquote class="background-transparent-darker-before">');
 	msg = msg.replace(/<\/blockquote>\s*/gm, '</blockquote>');
+
+	// Remove new-line between blockquotes.
 	msg = msg.replace(/<\/blockquote>\n<blockquote/gm, '</blockquote><blockquote');
+
+	// Replace linebreak to br
 	msg = msg.replace(/\n/gm, '<br>');
 
 	if (!_.isString(message)) {
@@ -56,6 +87,7 @@ export const original = (message) => {
 		message = msg;
 	}
 
+	// Support code blocks and inline code
 	message = code(message);
 
 	if (window && window.rocketDebug) {