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Bioinformatics: The science of developing computer databases and algorithms for the purpose of speeding up and enhancing biological research. Bioinformatics is being used most noticeably in the Human Genome Project, the effort to identify the 80,000 genes in human DNA . New academic programs are training students in Bioinformatics by providing them with backgrounds in molecular biology and in computer science, including database design and analytical approaches. (Definition from Whatis.com)
Bioinformatics: a combination of Computer Science, Information Technology and Genetics to determine and analyze genetic information. (Definition from BitsJournal.com)
Bioinformatics: is the science and technology about learning, managing and processing biological information. (Definition from Missouri University lecture)