Google Cloud Print is a Google service that lets users print from any Cloud-Print-aware application (web, desktop, mobile) on any device in the network cloud to any printer – without Google having to create and maintain printing subsystems for all the hardware combinations of client devices and printers, and without the users having to install device drivers to the client, but with documents being fully transmitted to Google. Since July 23, 2013 it also allows printing from any Windows application, if Google Cloud Printer is installed on the machine.
Google Cloud Print integrates with the mobile versions of Gmail and Google Docs, allowing users to print from their mobile devices. Google Cloud Print is listed as a printer option in the Print Preview page of Google's Web browser, Google Chrome, in Chrome 16 and higher. Printers without built-in Cloud Print support, often referred to as "legacy" or "classic", are supported through a "Cloud Print Connector" integrated with Google Chrome versions 9 and higher.
Google introduced Cloud Print in April 2010, as a future solution for printing from Chrome OS. Then they made the design document and a preliminary version of the source code available. Google Cloud Print reached beta stage on 25 January 2011.
Applications print through a web-based, common print dialog (web UI) or an API. The service forwards the job to a printer registered to the service. Cloud Ready printers (which connect directly to the web and do not require a computer to set up) can directly connect to Google Cloud Print. As legacy ("classic") printers cannot accept input from a cloud service, Google Chrome 9 contained a "Cloud Print Connector"—which lets printers plugged into a Microsoft Windows, Apple Mac, or Linux computer with Internet access use Cloud Print while the connector is running in Google Chrome.
Printing through Google Cloud Print from any instance of Google Chrome was enabled in Google Chrome 16.
In July 2013 Google updated the service to allow printing from any Windows application if Google Cloud Printer is installed on the machine. The Google Cloud Print Service can run as a Windows service, so legacy printers can connect to Google Cloud Print.
Google Cloud Print 2.0, not supported by some printers that support v 1.0, adds support for a local mode similar in operation to Apple's AirPrint. Unlike the earlier version of Cloud Print, v 2.0 does not require either the printer or printing client to be connected to the Internet. Local mode uses a discovery protocol called Privet, which uses Multicast DNS and DNS-SD for discovery, and HTTPS for transmitting print jobs to the printer. Clients supporting this mode only list printers that are discoverable on the same subnet the device is connected to, and forget the printers once disconnected from that subnet.
Documents printed via Google Cloud Print are sent to Google's servers for transmission to the printer. Google explains, "Google also keeps a copy of each document you send for printing - but only for so long as the printing job is active and not complete. We have to do this to make sure your document gets printed. Once the job is complete, the document is deleted from our servers...Documents you send to print are your personal information and are kept strictly confidential. Google does not access the documents you print for any purpose other than to improve printing."