O-ring and gaskets both achieve the same goal but o-rings are always rings with differing sizes where a gasket can be any shape or size.
8 Types of O-Ring + Applications (Clear Guide)
Gasket vs O-Ring: Which One to Choose
O-Rings? O-yeah! How to Select, Design, and Install O-Ring Seals – Tarkka
Nitrite vs Silicone Seals: Which Is Best?, Blog Posts
Quad Seals Compared to O-Ring Seals, Coating Systems
Value Collection Smooth Flange Bolt: 1/2-13 UNC, 1-1/2″, 46% OFF
O-ring VS Gasket: Which One Should You Use? - Hongju
Understand The Different Types Of O-Ring Materials
What's the Difference Between Viton and EPDM Seals?
Types of Gaskets for Flanges (Soft, Spiral, Ring Joint