This character is a Other Punctuation and is commonly used, that is, in no specific script.
The glyph is a wide version of the glyph Semicolon. Accordingly, its width in East Asian Text is fullwidth. In bidirectional text it acts as Other Neutral. When changing direction it is not mirrored. U+FF1B prohibits line breaks before its position. There might be some exceptions, though.
The Wikipedia has the following information about this codepoint:
The semicolon; (or semi-colon) is a symbol commonly used as orthographic punctuation. In the English language, a semicolon is most commonly used to link (in a single sentence) two independent clauses that are closely related in thought, such as when restating the preceding idea with a different expression. When a semicolon joins two or more ideas in one sentence, those ideas are then given equal rank. Semicolons can also be used in place of commas to separate items in a list, particularly when the elements of the list themselves have embedded commas.
The semicolon is one of the least understood of the standard marks, and is not frequently used by many English speakers.
In the QWERTY keyboard layout, the semicolon resides in the unshifted homerow beneath the little finger of the right hand and has become widely used in programming languages as a statement separator or terminator.