Amazon Kindle is a series of e-readers designed and marketed by Amazon. Amazon Kindle devices enable users to browse, buy, download, and read e-books, newspapers, magazines, Audible audiobooks, and other digital media via wireless networking to the Kindle Store. The hardware platform, which Amazon subsidiary Lab126 developed, began as a single device in 2007. Currently, it comprises a range of devices, including e-readers with E Ink electronic paper displays and Kindle applications on all major computing platforms. All Kindle devices integrate with Windows and macOS file systems and Kindle Store content and, as of March 2018, the store had over six million e-books available in the United States.