The at sign (@) is a computer symbol used in e-mail addresses that separates the user's name and the provider's address through an electronic mail system.
The arroba also refers to a unit of measurement widely used in agriculture and livestock to weigh cattle, pigs, fruit and today, in Brazil, it is equivalent to 15 kg.
At sign as E-mail symbol
It was in the computer age that the at sign "@" began to become very popular and part of the vocabulary of people and all keyboards in the world.
In this context, it was first used in the 70s, when the first email was sent by American computer Ray Tomlinson (1941-2016) with the first e-mail address: tomlinson@bbn-tenexa.
Note that this sign, in English, means "until”, that is, it indicates the place. Therefore, in emails, this symbol indicates the location of addresses.
In addition to email, nowadays the at sign is used, for example, in chats and forums, where the symbol is used before the person's name (@personname) so that the response is directed to that user specifically.
Other uses of the at sign are in social networks and in some programming languages.
If you want to know more about the topic, see also: Textual Genre Email
at sign as unit of measure
Although some think that this symbol is new, in fact, the origin of the “at” is related to commercial purposes and has existed since the 16th century.
Since then, the symbol has been widely used as a unit of measure. However, it was in the 19th century that it was added to typewriters and today we find it in all keyboards.
Thus, the “at” is an old measure of weight that is still used to indicate the mass, the amount of kilograms of something.
In Brazil, it is widely used to measure the weight of some animals or liquids, with 1 at sign equivalent to 15 kg, equivalent to 25 pounds.
Learn more about Units of Measure.
Origin and history of the arroba
Although the arroba was associated with commercial purposes in the 16th century, its specific origin is not known for sure.
Etymologically, the term may have arisen:
- from the French “until”, denoting the crased a “à”;
- of the Arabic language “air-rob”, to indicate “the fourth” of something;
- the abbreviation of the English expression "each at”, which means “each in”.
Some theories claim that this symbol would have appeared in the Middle Ages. The copyist monks, responsible for rewriting some manuscripts, were using this symbol as a way to abbreviate the Latin preposition “ad” which means “to”, “in” or “to”.
Thus, the letter “d” would represent the “tail” of the at sign. That's because the idea was to save the space available on the scrolls and, of course, seek efficiency in this process.
However, it was in a document dated 1536 that researchers found the use of this symbol indicating the amount of wine in a barrel. The document was supposedly written by Francisco Lapi, a Florentine merchant.
Since then, the at sign has been used to symbolize the weight of products sold and also to indicate the rate associated with them.