As a web platform, SharePoint Server is customizable. The look and feel of sites and collections can be standardized across your deployment using concepts such as Cascading Style Sheets (CSS) and master pages. When performing extensive customization of the SharePoint experience, you should spend time looking at the SharePoint development patterns and practices at https://docs.microsoft.com/en-us/sharepoint/dev/solution-guidance/sharepoint-development-and-design-tools-and-practices.
From a branding perspective, there are some key terms and concepts with which you should become familiar:
| Terminology | About |
| Alternate CSS | A CSS file other than the default that you can apply to the look and feel of your site. |
| Composed look | A combination of fonts, palettes, a background image, and an associated master page that can be applied to a site. |
| Content Search Web Part | A web part used to display content from search results. |
| corev15.css | The main CSS file that contains... |