Originally it was the length of the furrow in one acre of a ploughed field. An acre is an area that is one furlong long and one chain wide. For this reason, the furlong was once also called an acre's length. Around the year 1300, England standardised the furlong as 40 rods or 660 feet.
Vanilla sex is what a culture regards as standard or conventional sexual behaviour. Different cultures, subcultures and individuals have different ideas about what constitutes this type of sex. Often, it is interpreted as sex which does not involve such elements as BDSM, kink, or fetish activities.
In information technology, vanilla (pronounced vah-NIHL-uh ) is an adjective meaning plain or basic. The unfeatured version of a product is sometimes referred to as the vanilla version. The term is based on the fact that vanilla is the most popular or at least the most commonly served flavor of ice cream. Or, as Eric Raymond, editor of The New Hacker's Dictionary , puts it, the default ice cream.