1. A computerized method for designing a discrete droplet microfluidic system comprising the steps of: (a) providing an initial set of droplet based networks containing a first number of droplet based networks, wherein each droplet based network comprises one or more inlets, one or more outlets, two or more channels connected between the one or more inlets and the one or more outlets, and one or more bypass channels connected between the two or more channels; (b) coding each droplet based network into a data structure such that all the data structures form a current set of data structures; (c) creating one or more new data structures by performing one or more genetic operators on one or more selected data structures from the current set of data structures; (d) adding the one or more new data structures to the current set of data structures; (e) creating a new set of data structures that satisfies one or more design parameters for the discrete droplet microfluidic system and contains at least a second number of data structures selected from the current set of data structures, wherein the second number is less than a total number of data structures within the current set of data structures, wherein a first group of the new data structures are selected using a fitness score, a second group of the new data structures are selected using a combination of the fitness score and a diversity score, and a third group of the new data structures are selected randomly, and wherein the first group of the new data structures contains approximately 10% of the second number of data structures, the second group of the new data structures contains approximately 80% of the second number of data structures, and the third group of the new data structures contains approximately 10% of the second number of data structures; (f) replacing the current set of data structures with the new set of data structures; (g) repeating steps (c), (d), (e) and (f) until the new set of data structures has been created a third number of times; (h) displaying or outputting the current set of data structures as designs for the discrete droplet microfluidic system to one or more output devices; wherein steps (c), (d), (e), (f), (g) and (h) are executed by one or more processors communicably coupled to the one or more output devices; and fabricating the discrete droplet microfluidic system based on the displayed or outputted designs using a three-dimensional printer.