[Koha] Which Version of KOHA?

I would like to upgrade to KOHA on debian from Windows but I was wondering as to which version is stable so that I can install. Any advice please? -- Felix Chisoni Assistant Librarian, St Luke's College of Nursing and Midwifery P.O Box, 21 Chilema, Zomba, MALAWI. Tel:(+265)01539474 Cell: (+265)0888583137 (+265)0992255406 Email:felixchisoni@gmail.com/felixchisoni@yahoo.com