You can use any of the interactive visualizations from Our World In Data in your articles. This is possible because everything is permissively licensed (under CC-BY-SA) and because there is an easy embed feature on every chart.
Here are three recent examples of articles that embed OWID visualizations:
For example let's assume you want to write about fertility and on the fertility page you find this map that you want to embed in your own article:
At the bottom right of the chart you click the little income and then chose the option </>Embed. You will see a box popping up with the following bit of text:
<iframe src="https://ourworldindata.org/grapher/children-per-woman-UN" width="100%" height="600px"></iframe>
Now you just take this bit of html code and place it in the text of your own article.
An iframe is used to display a website within another website (w3schools has more info on iframes.) Similar to when you embed a YouTube video in your article, your article now embeds an Our World In Data visualization.
We try to make the embed tool as useful as possible: For example, you can focus on Africa instead of World in the map above; and you can move the time slider to 2015 (you will get this). Now when you click on </> Embed you get the following bit of code:
<iframe src="https://ourworldindata.org/grapher/children-per-woman-UN?region=Africa&year=2015" width="100%" height="600px"></iframe>
If you copy-paste this code your article will embed the map with a focus on Africa and the fertility rate for 2015.
And the same works for the chart view. Just switch to Chart in the visualization above and add the countries that you are interested in – like this. When you click on </> Embed you can now get the code to embed this line chart.
It is also possible to put static versions of Our World In Data visualizations in web articles, text documents or presentations. Just click on PNG below the chart and you have the chart that you need.