Answer:
Microarray technology is a very useful technology that allows to study the measure the expression levels of large numbers of genes simultaneously. It consists of a solid support (that can be glass, silice, or nylon), and to it are attached a lot of single stranded DNA fragments that acts like probes. By complementarity, the genes corresponding to this probes that are being expressed at some time will attach to it. Probe-target hybridization is usually detected and quantified by detection of a fluorophore compund, a silver stained, or chemiluminescence-labeled targets.