Depending on the configuration of your website, you may be able to publish to a stage site to view changes before you make them live.
When you click Publish or Save & Publish, a dialog will open giving you the choice to publish to Stage or Live.
If you choose live, the item will be published to both Stage and Live websites.
You can control when an item will appear and be removed by changing the Publish and Unpublish dates on the Publish Settings tab.
What happens when you publish
At publishing time, the item you are editing is versioned and marked as published.
If the item requires a page to be created, a new page will be generated automatically. The URL to this page appears when the Publish process is complete. Click on the link in the Publish dialog window. You can also view the page from the View tab in the item you are editing.
Any image resizing rules are also followed. These are defined by the creator of the template you chose when publishing the item. Images included in the item you are editing are copied and resized accordingly.