diff --git a/CHANGELOG.md b/CHANGELOG.md
index d3d07a1..d766712 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,3 +16,4 @@
 - support for `mdconf.json`config file
 - MathJax script to html
 - `mdconfig.json` extensions with `extends: "name"`
+- variables prefixed with `$` and system variables prefixed with `$$`
diff --git a/README.md b/README.md
index 7c7f987..889854b 100644
--- a/README.md
+++ b/README.md
@@ -74,6 +74,32 @@ You can include your own stylesheet. It is applied after the default style. The
 [!stylesheet]: path/to/style.css
 ```
 
+## Variables
+
+Variables are prefixed with `$`.
+You can define and use variables like this:
+
+Defining:
+```
+$varname = value
+$fruit = apple
+```
+
+Using:
+```
+I'm eating an $fruit.
+```
+
+There are system variables that are prefixed with `$$`.
+Currently you can use
+
+variable | value           | example value     
+---------|-----------------|--------------
+$now     | current datetime| 31.07.2019 21:03:47
+$date    | current date    | 31.07.2019
+$time    | current time    | 21:03:47
+
+
 ## Configuration file
 
 You can also define plugins, stylesheets and other stuff by using a `mdconf.json` file in the same directory as the main markdown file. Example config:
diff --git a/package-lock.json b/package-lock.json
index 4c59a3c..cbbc577 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -954,6 +954,11 @@
         "whatwg-url": "^7.0.0"
       }
     },
+    "date-format": {
+      "version": "2.1.0",
+      "resolved": "https://registry.npmjs.org/date-format/-/date-format-2.1.0.tgz",
+      "integrity": "sha512-bYQuGLeFxhkxNOF3rcMtiZxvCBAquGzZm6oWA1oZ0g2THUzivaRhv8uOhdr19LmoobSOLoIAxeUK2RdbM8IFTA=="
+    },
     "debug": {
       "version": "2.6.9",
       "resolved": "https://registry.npmjs.org/debug/-/debug-2.6.9.tgz",
@@ -3448,6 +3453,11 @@
       "resolved": "https://registry.npmjs.org/markdown-it-imsize/-/markdown-it-imsize-2.0.1.tgz",
       "integrity": "sha1-zKBCeQXQUziiR8ucqdloxc3dUXA="
     },
+    "markdown-it-inline-comments": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/markdown-it-inline-comments/-/markdown-it-inline-comments-1.0.1.tgz",
+      "integrity": "sha1-F26r5jGj4IElvXOVAPQ8UfUliW0="
+    },
     "markdown-it-ins": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/markdown-it-ins/-/markdown-it-ins-2.0.0.tgz",
@@ -3476,6 +3486,11 @@
       "resolved": "https://registry.npmjs.org/markdown-it-mathjax/-/markdown-it-mathjax-2.0.0.tgz",
       "integrity": "sha1-ritPTFxxmgP55HXGZPeyaFIx2ek="
     },
+    "markdown-it-modify-token": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/markdown-it-modify-token/-/markdown-it-modify-token-1.0.2.tgz",
+      "integrity": "sha1-VCRxoyMnClwQKmNbB/47R8J47qA="
+    },
     "markdown-it-multimd-table": {
       "version": "3.2.2",
       "resolved": "https://registry.npmjs.org/markdown-it-multimd-table/-/markdown-it-multimd-table-3.2.2.tgz",
diff --git a/package.json b/package.json
index 2cd3478..243bdce 100644
--- a/package.json
+++ b/package.json
@@ -30,6 +30,7 @@
     "@types/puppeteer": "^1.19.0",
     "argparse": "^1.0.10",
     "chokidar": "^3.0.2",
+    "date-format": "^2.1.0",
     "fs-extra": "^8.1.0",
     "jsdom": "^15.1.1",
     "line-by-line": "^0.1.6",
@@ -46,11 +47,13 @@
     "markdown-it-highlightjs": "^3.0.0",
     "markdown-it-implicit-figures": "^0.9.0",
     "markdown-it-imsize": "^2.0.1",
+    "markdown-it-inline-comments": "^1.0.1",
     "markdown-it-ins": "^2.0.0",
     "markdown-it-kbd": "^2.0.0",
     "markdown-it-mark": "^2.0.0",
     "markdown-it-math": "^4.1.1",
     "markdown-it-mathjax": "^2.0.0",
+    "markdown-it-modify-token": "^1.0.2",
     "markdown-it-multimd-table": "^3.2.2",
     "markdown-it-plantuml": "^1.4.1",
     "markdown-it-smartarrows": "^1.0.1",
diff --git a/src/configs/full-mdconfig.json b/src/configs/full-mdconfig.json
index 1102ab7..a7d4976 100644
--- a/src/configs/full-mdconfig.json
+++ b/src/configs/full-mdconfig.json
@@ -22,6 +22,7 @@
     "header-sections",
     "task-checkbox",
     "underline",
-    "implicit-figures"
+    "implicit-figures",
+    "inline-comments"
   ]
 }
diff --git a/src/lib/CommandParser.ts b/src/lib/PreFormatter.ts
similarity index 72%
rename from src/lib/CommandParser.ts
rename to src/lib/PreFormatter.ts
index 2f6c1d8..e9a341b 100644
--- a/src/lib/CommandParser.ts
+++ b/src/lib/PreFormatter.ts
@@ -6,11 +6,13 @@ import {pageFormats} from "./formats";
 import {PDFFormat} from "puppeteer";
 import {getMarkdownPlugin} from "./utils";
 import {logger} from "./logger";
+import {globalVariables} from "./globvars";
 
-export class CommandParser {
+export class PreFormatter {
     public projectFiles: string[];
     public pageFormat: PDFFormat;
     public stylesheets: string[];
+    public variables: any;
 
     private readonly resolvePath: {path: string, lines: number}[];
 
@@ -18,6 +20,7 @@ export class CommandParser {
         this.projectFiles = [];
         this.resolvePath = [];
         this.stylesheets = [];
+        this.variables = Object.assign({}, globalVariables);
     }
 
     async processCommands(doc: string, docpath: string, renderer: Renderer) {
@@ -44,25 +47,26 @@ export class CommandParser {
                     currentFile = this.resolvePath[this.resolvePath.length - 1];
                 }
             }
-            let match: RegExpExecArray = /\[ *!(\w+) *\]:? *(.*)/gu.exec(inputLine.replace(/\s/, ''));
+            let commandMatch: RegExpExecArray = /\[ *!(\w+) *\]:? *(.*)/g.exec(inputLine);
+            let variableMatch: RegExpExecArray = /\$(\w+) *= *(.*?) *$/g.exec(inputLine);
 
-            if (match && match[0]) { // TODO: stylesheets
-                switch(match[1]) {
+            if (commandMatch && commandMatch[0]) {
+                switch(commandMatch[1]) {
                     case 'use':
-                        let plugins = match[2].split(',');
-                        logger.verbose(`Adding plugins: ${match[2]}`);
+                        let plugins = commandMatch[2].split(',');
+                        logger.verbose(`Adding plugins: ${commandMatch[2]}`);
                         for (let mdPlugin of plugins) {
                             renderer.addPlugin(getMarkdownPlugin(mdPlugin.replace(/^ *| *$/g, '')));
                         }
                         break;
                     case 'include':
                         try {
-                            if (!this.resolvePath.find(x => x.path === match[2])) { // if the include is in the path, it is a circular reference
-                                let included = await this.getInclude(match[2], mainDir);
+                            if (!this.resolvePath.find(x => x.path === commandMatch[2])) { // if the include is in the path, it is a circular reference
+                                let included = await this.getInclude(commandMatch[2], mainDir);
                                 inputLines.unshift(...included);
-                                this.resolvePath.push({path: match[2], lines: included.length});
+                                this.resolvePath.push({path: commandMatch[2], lines: included.length});
                             } else {
-                                logger.warning(`Circular reference detected. Skipping include ${match[2]}`);
+                                logger.warning(`Circular reference detected. Skipping include ${commandMatch[2]}`);
                             }
                         } catch (err) {
                             logger.error(err.message);
@@ -70,28 +74,40 @@ export class CommandParser {
                         }
                         break;
                     case 'format':
-                        if (!this.pageFormat && Object.values(pageFormats).includes(match[2]))
+                        if (!this.pageFormat && Object.values(pageFormats).includes(commandMatch[2]))
                             // @ts-ignore
-                            this.pageFormat = match[2];
+                            this.pageFormat = commandMatch[2];
                         else
-                            logger.warning('Invalid page format or format already set: ' + match[2]);
+                            logger.warning('Invalid page format or format already set: ' + commandMatch[2]);
                         break;
                     case 'newpage':
                         renderer.addPlugin(getMarkdownPlugin(markdownPlugins.div));
                         outputLines.push('::: .newpage \n:::');
                         break;
                     case 'stylesheet':
-                        await this.addStylesheet(match[2], mainDir);
+                        await this.addStylesheet(commandMatch[2], mainDir);
                         break;
                     default:
                         outputLines.push(inputLine);
                 }
+            } else if (variableMatch) {
+                this.variables[variableMatch[1]] = variableMatch[2];
+                logger.debug(`Added variable: "${variableMatch[1]}": "${variableMatch[2]}"`);
             } else {
                 outputLines.push(inputLine);
             }
         }
 
-        return outputLines.join('\n');
+        let documentContent = outputLines.join('\n');
+        // replacing all variables with their values.
+        for (let [key, value] of Object.entries(this.variables)) {
+            let varReplacer: RegExp = new RegExp(`\\$${key}`, "gi");
+            if (typeof  value === "function")
+                value = await value();
+            // @ts-ignore
+            documentContent = documentContent.replace(varReplacer, value);
+        }
+        return documentContent;
     }
 
     /**
diff --git a/src/lib/Renderer.ts b/src/lib/Renderer.ts
index 6ec5863..b71e2a6 100644
--- a/src/lib/Renderer.ts
+++ b/src/lib/Renderer.ts
@@ -4,7 +4,7 @@ import * as path from 'path';
 import * as chokidar from 'chokidar';
 import * as puppeteer from 'puppeteer';
 import {JSDOM} from 'jsdom';
-import {CommandParser} from "./CommandParser";
+import {PreFormatter} from "./PreFormatter";
 import {EventEmitter} from "events";
 import {PDFFormat} from "puppeteer";
 import {MarkdownConfig} from "./MarkdownConfig";
@@ -15,7 +15,7 @@ export class Renderer extends EventEmitter {
     private md: MarkdownIt;
     private readonly beforeRendering: Function[];
     private readonly afterRendering: Function[];
-    private commandParser: CommandParser;
+    private commandParser: PreFormatter;
     private config: MarkdownConfig;
 
     constructor(config?: MarkdownConfig) {
@@ -24,7 +24,7 @@ export class Renderer extends EventEmitter {
         this.md = new MarkdownIt();
         this.beforeRendering = [];
         this.afterRendering = [];
-        this.commandParser = new CommandParser();
+        this.commandParser = new PreFormatter();
         this.configure();
     }
 
diff --git a/src/lib/globvars.ts b/src/lib/globvars.ts
new file mode 100644
index 0000000..e69de29
diff --git a/src/lib/plugins.ts b/src/lib/plugins.ts
index 9eb584f..db374a7 100644
--- a/src/lib/plugins.ts
+++ b/src/lib/plugins.ts
@@ -70,5 +70,8 @@ export const markdownPlugins: any = {
         options: {
             figcaption: true
         }
+    },
+    'inline-comments': {
+        module: 'markdown-it-inline-comments'
     }
 };
diff --git a/src/styles/default.sass b/src/styles/default.sass
index f549476..259f541 100644
--- a/src/styles/default.sass
+++ b/src/styles/default.sass
@@ -36,6 +36,9 @@ figcaption
   margin: 0.5em
   font-style: italic
 
+.footnote-backref
+  display: none
+
 .page
   page-break-before: always
   page-break-after: always