Bay of Pigs. Kennedy didnât wait long for the first confrontation of his presidency. Only weeks after he took office he was told of a secret CIA plan to send an army of Cuban exiles to overthrow Fidel Castro and rid the western hemisphere of its first Communist regime.
An enumeration district, as used by the Bureau of the Census, was an area that could be covered by a single enumerator (census taker) in one census period. Enumeration districts varied in size from several city blocks in densely populated urban areas to an entire county in sparsely populated rural areas. Enumeration district maps show the boundaries and the numbers of the census enumeration districts, which were established to help administer and control data collection.
An enumeration is treated as a bit field; that is, a mask comprised of a set of flags. The results from bitwise operations are also bit fields. Bit fields are generally used for lists of elements that might occur in combination, whereas enumeration constants are generally used for lists of mutually exclusive elements.