You should read the following discussion and analysis of our financial condition and results of operations together with the consolidated financial statements and related notes that are included elsewhere in this Annual Report on Form 10-K. This discussion contains forward-looking statements based upon current expectations that involve risks and uncertainties. Our actual results may differ materially from those anticipated in these forward-looking statements as a result of various factors, including those set forth under "Risk Factors" included in Part I, Item 1a or in other parts of this Annual Report on Form 10-K.
We have pioneered the next generation of network security with our innovative platform that allows enterprises, service providers, and government entities to secure their networks and safely enable the increasingly complex and rapidly growing number of applications running on their networks. The core of our platform is our Next-Generation Firewall, which delivers application, user, and content visibility and control as well as protection against cyber threats integrated within the firewall through our proprietary hardware and software architecture. Our products and services can address a broad range of our end-customers' network security requirements, from the data center to the network perimeter, as well as the distributed enterprise, which includes branch offices and a growing number of mobile devices. We derive revenue from sales of our products and services, which together comprise our platform. Product revenue is primarily generated from sales of our Next-Generation Firewall which is available in hardware and virtualized platforms. All of our products incorporate our proprietary PAN-OS operating system, which provides a consistent set of capabilities across our entire product line. These capabilities include: application visibility and control (App-ID), user identification (User-ID), site-to-site VPN, remote access SSL VPN, and Quality-of-Service (QoS). Our products are designed for different performance requirements throughout an organization which range from the PA-200, which is designed for enterprise remote offices, to the PA-5060, which is designed for high-speed data centers. The same firewall functionality that is delivered in the hardware platforms is also available in the VM-Series virtual firewalls which secure virtualized and cloud-based computing environments. Multiple firewalls can leverage the WildFire appliance, WF-500, which identifies, analyzes, and blocks known and unknown malware in a private cloud-based environment. Our platform can be centrally managed in both virtualized and hardware platforms across an organization with our Panorama product. Services revenue includes sales of subscriptions and support and maintenance. Our Threat Prevention, URL Filtering, GlobalProtect, and WildFire subscriptions provide our end-customers with real-time access to the latest antivirus, intrusion prevention, web filtering, and modern malware prevention capabilities across fixed and mobile devices. When end-customers purchase a product, they typically purchase one or more of our subscriptions for additional functionality, as well as support and maintenance in order to receive ongoing security updates, upgrades, bug fixes, and repairs. Sales of these services increase our deferred revenue balance and contribute significantly to our positive cash flow provided by operating activities.