ISTQB is the International Software Testing Qualification Board. ISQTB is a not for profit organisation made up of volunteers, based in Brussels. ISTQB maintain an international qualification scheme specifically for software and system testing professionals which is comprised of three levels, Foundation, Advanced and Expert with three streams through the levels, Agile, Core and Specialist.
The ISTQB is made up of local boards, each one representing a geography or geographies. UKITB is the local board representing the United Kingdom software testers.