When the cursor is hovering text which can be edited inline, an edit cursor appears:
Inline editing improves the user experience during editing of page contents. Inline editing enables the content editor to change content directly on the page. In particular, the content editor avoids to open the form-based content editor - which of course can still be used.
Clicking the inline editable field, the text is highlighted and optionally a format toolbar comes up:
If configured, the inline editor also shows edit points on the content which allow alteration of additional content fields. Via the inline editor's toolbar you can open the form-based content editor to get access to all content fields.
Here is a demo of the inline editor.
Inline editing can be enabled for content fields of types OpenCmsString and OpenCmsHtml which are usually the fields exposing text. For all other content fields, including whole nested content, the inline editor can show edit points at places that are configurable.
Images can be replaced via drag & drop, if configured as described here.