Synthetic oligonucleotides act as a fuel for engine of modern molecular biology. One of the major application of these biomolecules is in construction of oligonucleotide microarrays or biochips. Microarrays are monolithic, flat surfaces that bear multiple probe sites and each bear a reagent whose molecular recognition of a complementary molecule can result to a signal that is detected by an imaging technology, most often fluorescence. Large-scale genotyping, gene-expression profiling, and disease diagnosis are some of the main applications of biochips. At the present time, this technology of arrayed nucleic acids is employed in many areas, from genetics to molecular medicine to industrial production. This book will give you an insight to efficient strategies for microarray fabrication using modified/unmodified oligonucleotides and glass microslides. In addition, chemical reagents for the estimation of functional group density on solid supports are discussed.