Update README.md

Author: quinnj

README.md

@@ -1 +1,20 @@
 # JSONTables.jl
+
+A package that provides a JSON integration with the [Tables.jl](https://github.com/JuliaData/Tables.jl) interface, that is, it provides the `jsontable` function as a way to treat a JSON object of arrays, or a JSON array of objects, as a Tables.jl-compatible source. This allows, among other things, loading JSON "tabular" data into a DataFrame, or a JuliaDB table, or written out directly as a csv file.
+
+JSONTables.jl also provides two "write" functions, `objecttable` and `arraytable`, for taking any Tables.jl-comptabile source (e.g. DataFrame, ODBC.Query, etc.) and writing the table out either as a JSON object of arrays, or array of objects, respectively.
+
+So in short:
+```julia
+# treat a json object of arrays or array of objects as a "table"
+jtable = jsontable(json_source)
+
+# turn json table into DataFrame
+df = DataFrame(jtable)
+
+# turn DataFrame back into json object of arrays
+objecttable(df)
+
+# turn DataFrame back into json array of objects
+arraytable(df)
+```