CKEditor is a truly flexible tool with a modular structure — most editor functionality is based on plugins. Some core plugins are necessary for the editor to work or depend on one another, however, there are lots of optional plugins that you can skip when you do not need the functionality that they provide.
If you want to disable some functionality that comes from a CKEditor plugin, you can use the removePlugins setting to prevent the plugin from loading.
// Remove one plugin. config.removePlugins = 'elementspath'; // Remove multiple plugins. config.removePlugins = 'elementspath,save,font';