Why is Specific Gravity Important?

[imsmooth]

I asked this once before, but forgot the answer.

I know the difference between the two. I would like to know why S.G. is even relevant since it seems to give the same answer as density.
Ex. Density of a fluid is 10 g/cm3 and density of water at 4C is 1g/cm3 so the S.G. of the fluid is 10 (no units)

So what is the point?

 

[Svein]

I asked this once before, but forgot the answer.

I know the difference between the two. I would like to know why S.G. is even relevant since it seems to give the same answer as density.
Ex. Density of a fluid is 10 g/cm3 and density of water at 4C is 1g/cm3 so the S.G. of the fluid is 10 (no units)

So what is the point?

So who decided that water at 4°C is the measuring stick?

 

[nasu]

The point is that only in Si units the specific gravity is numerically equal to the density of water.
Specific gravity show right away if the object floats or sink in water, no matter what units you use for density (lb/ft^3 for example).