Attaché case

A briefcase is a narrow hard-sided box-shaped bag or case used mainly for carrying papers and other documents and equipped with a handle. Lawyers commonly use briefcases to carry briefs to present to a court, hence the name. Businesspeople and other professionals also use briefcases to carry usually important papers, and in more recent times electronic devices such as laptop computers and tablets.

Briefcases are descendants of the limp satchel used in the fourteenth century for carrying money and valuables. It was called a "budget", derived from the Latin word "bulga" or Irish word "bolg", both meaning leather bag (the Irish also means 'stomach'), and also the source of the financial term "budget".

Godillot of Paris was the first to use a hinged iron frame on a carpet bag in 1826. There then followed the Gladstone bag and the Rosebery, an oval-top bag. Eventually these became the modern metal-framed briefcase. The first of what is known as the modern rectangular briefcase is said to have been invented in the late 1850s. In 2014 the global business bag market was $9.4 billion.

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Wikipedia