It can act as a simple breakout board for either a single SSOP-20 or x2 SOT-23-6 chips. To use it as a normal breakout just use solder to bridge the 20 connectors on the right and left and sides of the board and it will be a normal breakout (which each pin on the chip going to one of the header pins directly).
However there is also a SMT grid on the front and back so you can solder a full circuit onto the chip and arbitrarily have any point in the circuit wired to the various pins. Which makes for very handle little modules you can solder up and reuse.
I also added two power rails for ground and VCC down the middle with vias to both sides of the board. I also added other connectors around the edge that add in vias and wires connections to the opposite side of the board. Should be very useful.
One other little hidden feature is the spacing. Most of the pads are the perfect size to fit most two terminal SMT components (x4 0603 components can solder onto a single pad). But because the pads down the middle are offset it is also very easy to solder on SOT-23 connectors that have 3 terminals. So you really can solder almost any sort of SMT components on here.
Next step will be to build a larger protoboard that can accept modules like this and similar to create more advanced circuits.