Masonic rings are just like any other type of ring. What makes them different is the symbol that's on them or the general theme.
There are many types of Masonic Rings. Some rings have symbols that stand for a separate organization within the freemasonry.
Examples of these are the Scottish Rite Rings, York Rite Rings, Shrine Rings, Templar Rings, and Eastern Star Rings. Usually the symbol will be integrated in the ring like the one below.
Masonic Rings can also represent degrees like the Master Mason Ring, which usually has the regular square and compass symbol engraved on it.
Examples of these are the Blue Lodge Rings(e.g. Master Mason Ring) and Past Master Rings.