NOVELTY - A composition comprises a first area of a first substrate adhered to a second area of a second substrate, where the first area is tacky or comprises an array of tapered protrusions on it, where the second area comprises an array of tapered protrusions or tapered grooves on it.    USE - As adhesive composition (claimed) in biomedical applications such as wound dressings and sutures, for bone repair and grafts; and in electronics, displays, photovoltaics, light emitting diodes, lighting, optics, consumer products, batteries, semiconductors, fuel cells, antennas, curved surfaces, cell biology, medical applications, proteomics, diagnostics and sensors.    ADVANTAGE - The composition and adhesive system is impermeable to a liquid. The tapered protrusions or tapered grooves are free from barbs, hooks, spirals, loops, seta, spatulae, suction cups, or any other external structural elements. The first and second elements are biodegradable and thus able to degrade or break apart in the body into inert substances that are easily passed or cleared. This allows for the use of adhesive composition in biomedical applications. The composition when contacted with liquid, maintains a seal between two arrays such that the liquid is not able to permeate the seal. This allows for the preparation of system that will keep liquids from leaking across the adhered area thereby providing a liquid tight seal that can either retain liquids or keep them away from a sealed area. The composition allows for adhesion between two separate substrates (e.g. articles of clothing, metal, glasses, ceramics, polymers, or semiconductors) or two separate portions of the same substrate e.g. skin to form suture.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) a method of preparing the composition involving: providing the first area of the first substrate; providing the second area of the second substrate; and contacting the first area with the second area;    (2) a method (M1) of preparing an adhesive system comprising at least one adhesive element, involving: disposing a moldable material on a substrate; contacting the moldable material with a master having a pattern of indentations in it, where the moldable material conforms to a three-dimensional shape of the pattern of indentations; removing the master from the moldable material to provide an adhesive element including an array of tapered protrusions or tapered grooves on the substrate, where the tapered protrusions or tapered grooves have a base portion attached to the substrate, a tip portion, and a tapered body portion connecting the tip and base portions, where the protrusions or grooves have a vertical dimension of about 1 mu m to about 500 mu m, where the base portion of the protrusions or grooves have a lateral dimension of about 1 mu m to about 100 mu m, where the protrusion or grooves are free from barbs, hooks, spirals, loops, seta, spatulae, suction cups, or any other external structural elements, and where the tapered body portion of the protrusions have a tapered sidewall having an average angle of taper of about 5 degrees to approaching 90 degrees ;    (3) an adhesive system comprising: a first adhesive element having a surface including an array of tapered protrusions on it; a second adhesive element having a surface including an array of tapered protrusions or tapered grooves on it, where contacting either of the first or second adhesive elements with an inert surface results in an adhesive interaction having a force per unit area of less than 50% of the adhesive interaction with a complementary adhesive element; and    (4) a kit comprising the adhesive system.