How do I set up content that is common on every page?

Hi!

I'm currently trying to migrate content from a SS 5.0 site (www.matterofstats.com) to SS 6.0 but am unsure how to set up the sidebar content on every page.

Most of the content is static. However, the Latest Information image is updated every week and the last thing we want to do is update this image on every page showing the sidebar every week.

Is there a way in SS 6.0 to set up this content so it only needs to be updated in one place and then the change be propogated to other pages?

We are using the Beatrice template for the new SS 6.0 site.

Thank you.