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+# unit.h
+
+unit.h is a simple library for working with units and dimensioned quantities in C.
+
+To use it, simply copy the `unit.h` file into your project and include it where necessary. 
+You must also define the `UNITH_IMPL` macro before importing it in one file so the 
+implementation is compiled.
+
+## Working with dimensioned quantities
+
+unit.h provides the U-macro, which accepts a string representing a unit or compound 
+unit and returns the conversion ratio between it and the corresponding SI unit. This 
+conversion ratio can be used to construct dimensioned quantities like so:
+
+```
+double water_density = 1.0 * U("g/cm^3");
+```
+
+Likewise, the UFMT and UARG macros can be used with `printf` to display these quantities 
+like so:
+
+```
+printf("The density of water is " UFMT ".\n", UARG(water_density, "kg/m^3"));
+```
+
+## Unit Strings
+
+Units are defined as c-strings. Each string consists of a series of unit names separated 
+by whitespace, each unit may be raised to an arbitrary (non-)integer power with a 
+`^`. There may also be a single slash among the units, which negates the exponenents 
+of all following units.
+
+In the case where there are no units before the slash, the number 1 must be used 
+before it instead: "1/cm^3".
+
+## Misc. Notes
+
+Angular measurements are internally represented using radians and steradians so they 
+can work with trigonometric functions.
+
+SI prefixes may be used before unit names. (E.g. "Mm" is a megameter.)
+