This is a Page in WordPress, chosen (in Settings > Reading) to be the front page of the site. Unlike the rest of the site, the sidebar has been turned off for this page (via the page’s Layout Settings).
Unlike Posts or news stories, Pages do not display the author or publication time, and are not automatically indexed in chronological order. Instead, they can be organized through the Parent page attribute and Menus to create the site’s navigational structure.
Pages have the same full WYSIWYG formatting capabilities as posts, including insertion of images, videos, gallery sliders and forms. The page’s feature image, if selected, is displayed above the headline.