Pity the poor semicolon—so often misunderstood, so seldom asked to dance because he is seen as stiff, formal and pretentious.
But he’s such a practical, useful fellow whose talents should be appreciated. I would like to reintroduce him to you.
A semicolon has two primary functions, exemplified in two labels attached to it: It is said to be the equivalent of a weak period and a strong comma. Think of the two as distinct dance steps.
In its weak-period mode, the semicolon stands in for a period when an independent clause could appear as a separate sentence but is so closely related to the previous independent clause that the semicolon is inserted to signal that relationship:
“An investigator files and locates court documents; librarians file claims for missing serials and locate requested information.”
As a stand-in for a strong comma, it separates items in a list when one or more items in that list are themselves lists:
“The apple figures prominently in Christian and Islamic belief; Greek, Nordic, and Celtic legends; and folklore throughout the Western world.”
It serves that function, too, when one or more list items otherwise include a comma: