For Ms. Lett, college represented a door to a better world, but the application process was a forbidding mystery.
The concept of peelings defines the title of Onion Skin, but DELTΔ earns it's name from a more arcane source: "Originating from the equivalent letter of the Phoenician alphabet," Ratsi writes, "it is based on a hieroglyph initially representing a door".
Partnering with Sky represents a back door into the television market.
Eurosceptics claim it represents an open door for criminals and terrorists.
Last year a few hypotheses emerged regarding such a trip, including a visit to Paris and its suburbs, to Lourdes and to a city that no pope has yet visited, such as Marseille, which represents an open door to the world.
Last but not least, Cadbury is releasing 24 Cadbury purple trucks, on for each day leading up to Christmas with each truck representing a different door of a Cadbury advent calendar.
It is important to note that we can no longer assume that the FBI and the CIA and the NSA work, first of all, for the safety of the American people; they also now represent a revolving door of government officials who become security industry lobbyists and manufacturers, which, in turn, get the multimillion-dollar contracts for tackling the very problems these stories appear to highlight.
Indeed, some analysts suggest the central bank's new lending program represents a kind of back door to the easy-money policy pursued by the Federal Reserve after the collapse of Lehman Brothers in 2008, which is widely credited with averting a broader economic disaster.
As the world moves from web to apps owning this "front door" represents a huge commercial opportunity; notifications will drive both engagement and revenue for the next generation of mobile companies.
Welsh-language campaigners suspect the deal, cooked up they say by the BBC and S4C behind closed doors, represents a major threat to the independence of what they see as their national broadcaster.
