The semicolon or semi-colon (;) is a punctuation mark that separates major sentence elements. A semicolon can be used between two closely related independent clauses, provided they are not already joined by a coordinating conjunction. Semicolons can also be used in place of commas to separate the items in a list, particularly when the elements of that list contain commas.

The first printed semicolon was the work of the Italian printer Aldus Manutius the Elder in 1494. Manutius established the practice of using the semicolon to separate words of opposed meaning and to allow a rapid change in direction in connecting interdependent statements. Ben Jonson was the first notable English writer to use the semicolon systematically. The modern uses of the semicolon relate either to the listing of items or to the linking of related clauses.

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