Matt (10 & 20 Sheen)
This level of gloss has no shine or has very little shine. Sheen level of 10 is referred as Dead Matt and has a flat, velvet-like finish. Sheen level of 20 is referred as Normal Matt where some coating is visible. However, three coats of matt varnish will produce a sheen that is the equivalent to the next level of sheen called Satin.
Satin (30 Sheen)
Eggshell is another way to describe satin. This is because the sheen level is about the same as the surface of an egg on an application of a single coat. However, three coats is a bit shinier.
Semi-Gloss (60 Sheen)
It is a level of gloss where there is a traditional glossy-look but it is not really a high gloss. The sheen level is also referred as a buttery gloss. The edges and carving areas get highlighted in a better way in this sheen level.
Gloss (> 85 sheen)
It is a level of gloss with very shiny and reflective surface. If you hold an object against a piece of wood that had two to three coats of a gloss varnish applied, a clear reflection of the object is produced on the wood.