Twin vs Vác

Informations

Twins are two offspring produced by the same pregnancy. Twins can be either monozygotic ('identical'), meaning that they develop from one zygote, which splits and forms two embryos, or dizygotic ('non-identical' or 'fraternal'), meaning that each twin develops from a separate egg and each egg is fertilized by its own sperm cell.

In contrast, a fetus that develops alone in the womb (the much more common case, in humans) is called a singleton, and the general term for one offspring of a multiple birth is a multiple. Unrelated look-alikes whose resemblance parallels that of twins are referred to as doppelgangers.

Source: Wikipedia

Informations

This is a list of auxiliaries of the United States Navy. It covers the various types of ships that support the frontline combat vessels of the United States Navy. Auxiliary ships which function as hospital ships and as oilers are to be found in their own articles: List of United States Navy hospital ships and List of United States Navy oilers. Escort carriers, amphibious warfare vessels, and some mine warfare vessels were also originally classed as auxiliaries but were later given their own hull classification symbols outside the auxiliary series (which all begin with an 'A'). Links to these and other list articles of similar ships can be found throughout this article. Yard and district craft also function as auxiliaries but generally are smaller and less capable than their ocean-going counterparts, and so they generally remain in harbors and coastal areas.

Their hull classification symbols begin with a 'Y'. Ship status is indicated as either currently active [A], ready reserve [R], inactive [I], or precommissioning [P]. Ships in the inactive category include only ships in the inactive reserve, ships which have been disposed from US service have no listed status. Ships in the precommissioning category include ships under construction or on order. Listed ship classes will often state 'MA type' or 'MC type'. The difference is that 'MC Type' refers to ships designed by the United States Maritime Commission aka MarCom, while 'MA Type' refers to ships designed or converted under MarCom's successor agency, the United States Maritime Administration or MarAd. They are in fact the same designs, and the year 1950 is the date at which MarAd succeeded MarCom.

Source: Wikipedia