and/or
The slashed pair meant to cover “one, the other, or both.”
Avoid and/or in ordinary prose. Use or, or both, or recast the sentence. Keep and/or in legal, technical, or form language where the three-way choice must be unmistakable and space is tight.
Examples
Use Bring a passport or a license, or both.
Prefer Fines, jail, or both may apply.
Avoid Bring a passport and/or a license.
Critics call the slash ugly; defenders call it precise. Precision is real in statutes and checklists. It is rarely needed in a paragraph.