Biochips are advanced technologies that integrate biotechnology and micro-miniaturization to perform thousands of simultaneous biochemical tests, acting as miniaturized laboratories. They are categorized into DNA microarrays, protein microarrays, and microfluidic chips, with applications in diagnostics, clinical research, drug development, and toxicology studies. The cost of biochips is decreasing, with potential future standardization leading to even lower prices as genes and SNPs are better understood.