And/or is an English grammatical conjunction used to indicate that one, more, or all of the cases it connects may occur. It is used as an inclusive or (as in logic and mathematics), because saying "or" in spoken or written English might be inclusive or exclusive.
The construction has been used in official, legal, and business documents since the mid-19th century, and evidence of broader use appears in the 20th century.[1] It has been criticized as both ugly in style—by many style guides, including the classic The Elements of Style (from William Strunk, Jr. and E.B. White)—and ambiguous in legal documents—by American and British courts.