Google Slides (formerly known as Google Presentations) is a browser based presentation program running as cloud service, launched in 2007. It is part of Google's office programs suite Docs which in turn is part of the company's larger service package Google Drive which also offers cloud storage.
With Google Slides you can create presentations, publish them on the web and share with your audience or partners.
Google Slides has also been published as Web, Android, and iOS versions. It is also available as a Chrome browser add-in. Since 2013 Google Slides can be edited also off-line. A presentation is updated when back on-line.
Other similar services include Microsoft PowerPoint Online, Slideshare, and Prezi.