Quick launch is a configurable navigation element in SharePoint.
Quick launch is a configurable navigation element in SharePoint looking like the following:
If you're the site owner or have edit permissions on a SharePoint site, you can customize the navigation for your site to give users quick access to sites and pages. You can add, edit, or remove links on the left-hand menu on a team site (also known as the Quick Launch menu). You can read more about Customizing the navigation on your SharePoint site, here.
Questions having the tag quick-launch regards all aspects of quick launch in SharePoint.