Dropbox

Dropbox is a file hosting service operated by Dropbox, Inc., that offers cloud storage, file synchronization, and client software. Dropbox allows users to create a special folder on each of their computers, which Dropbox then synchronizes so that it appears to be the same folder (with the same contents) regardless of which computer is used to view it. Files placed in this folder also are accessible through a website and mobile phone applications.
Dropbox, Inc., was founded in 2007 by MIT students Drew Houston and Arash Ferdowsi, as a Y Combinator startup company.
Dropbox provides client software for Microsoft Windows, Mac OS X, Linux, Android, iOS, BlackBerry OS and web browsers, as well as unofficial ports to Symbian, Windows Phone and MeeGo.
According to Dropbox, founder Drew Houston conceived the idea after repeatedly forgetting his USB flash drive while he was a student at MIT. He says that existing services at the time "suffered problems with Internet latency, large files, bugs, or just made me think too much." He began making something for his personal use, but then realized that it could benefit others with the same problems. Houston founded Dropbox, Inc. in June 2007, and shortly thereafter secured seed funding from Y Combinator.Dropbox officially launched at 2008's TechCrunch50, an annual technology conference.
Due to trademark disputes between Proxy, Inc. and Evenflow (Dropbox's parent company), Dropbox's official domain name was "getdropbox.com" until October 2009, when they acquired their current domain, "dropbox.com".
OPSWAT reported in their December 2011 market share report that Dropbox held 14.14% of the worldwide backup client market, based on number of installations.
In May 2011, Dropbox struck deals with Japanese mobile service providers Softbank and Sony Ericsson. As per the terms of the deal Dropbox will come preloaded on their mobile telephones.
In May 2010, Dropbox users in China were unable to access Dropbox. Later, Dropbox confirmed they had been blocked by the Chinese government. Due to the fact that the censorship usually focuses on popular services only, many considered this evidence of Dropbox's rapidly rising popularity and international user base.As of January 2013, the website is still blocked in China, but locally installed applications are usable with some ISPs.^{[citation needed]}
As of October 2011, Dropbox had more than 50 million registered users.
In April 2012, Dropbox announced a new feature allowing users to automatically upload photographs or videos from camera, tablet, SD card, or smartphone. Users will be given up to 3 GB (initially 5 GB) extra space to accommodate the photographs and videos uploaded in this fashion, but the space is permanently added to the user's allowance and is not restricted to pictures. It is viewed as a move against Google's recently launched Google Drive and Microsoft's SkyDrive.
As of 26 September 2012, Facebook and Dropbox integrated to allow group users to share files to Facebook Groups using Dropbox’s cloud-based storage system. The feature allows users to directly share inside Facebook's group pages without exiting the Facebook domain. This did not replace the built in Facebook uploading feature, but added to it for any files that were already uploaded to their Dropbox storage account.
On 12 November 2012, Dropbox announced it had reached 100 million users.
On December 19, 2012 Dropbox acquired the photo cloud storing giant Snapjoy. Snapjoy allows users aggregate, archive and view all digital photographs taken from cameras, phones or popular photo apps and view them online, or via an app, in one location. Financial terms were not released at the time of the acquisition.
As of February 2013, Dropbox was responsible for 0.29% of all worldwide internet bandwidth.
On March 15, 2013 Dropbox acquired the email management application for iOS Mailbox.

Financials

Dropbox has received a total venture capital funding of US$257.2 million from several investors, including Y Combinator, Sequoia Capital and Accel Partners.
In 2011 it was speculated that Dropbox's valuation was more than $1 billion.TechCrunch, VentureBeat, Business Insider and Financial Post speculated that Dropbox's valuation could be up to $5 to $10 billion.
Dropbox's 2011 revenue was expected to be $240 million.
Dropbox is based in San Francisco, and is funded by Sequoia Capital, Accel Partners, and Amidzad.Starting in mid-2009, they began releasing new features gradually to help measure customer interest, a Lean Startup technique.
On April 3, 2012, Dropbox announced Bono and The Edge, two members of the Irish rock band U2, were individual investors in the company

Technology

Both the Dropbox server and desktop client software are primarily written in Python. The desktop client uses GUI toolkits such as wxWidgets and Cocoa. Other notable Python libraries include Twisted, ctypes, and pywin32. Dropbox ships and depends on the librsync binary-delta library (which is written in C).
The Dropbox client enables users to drop any file into a designated folder that is then synchronized with Dropbox's Internet service and to any other of the user's computers and devices with the Dropbox client. Users may also upload files manually through a web browser.
Dropbox client supports synchronization and sharing along with personal storage. It supports revision history, so files deleted from the Dropbox folder may be recovered from any of the synced computers.
Dropbox supports multi-user version control, enabling several users to edit and re-post files without overwriting versions.The version history is by default kept for 30 days, with an unlimited version called "Pack-Rat" available for purchase.
The version history is paired with the use of delta encoding technology. When a file in a user's Dropbox folder is changed, Dropbox only uploads the pieces of the file that are changed when synchronizing, when possible.
Dropbox uses Amazon's S3 storage system to store the files; though Houston has stated that Dropbox may switch to a different storage provider at some point in the future. It also uses SSL transfers for synchronization and stores the data via AES-256 encryption, though this is done with Dropbox's own encryption keys, and not the users'.
Dropbox also provides a technology called LANSync,^{[citation needed]} which allows computers on a local area network to securely download files locally from each other instead of always hitting the central servers. LANSync was developed by Dropbox Engineer Paul Bohm.