Adding a table to the github-page - markdown right or wrong!?

i want to add a table on my github-page

similar to this page i want to do things. - see the table


---
title: Publishing on Github Pages
sidebar: mydoc_sidebar
permalink: mydoc_publishing_github_pages.html
summary: "You can publish your project on Github Pages, which is a free web hosting service provided by Github. All you need is to put your content into a Github repo branch called gh-pages and make this your default branch in your repo. With a Jekyll site, you just commit your entire project into the gh-pages branch and Github Pages will build the site for you."
folder: mydoc
---

this should look like so

but belive it or not - it looks like so - if i put the above mentioned code on my github-readme page

what do i wrong - which mistake is here!?