O2 (UK) they can do it too" in reference to Vodafone and EE, O2's biggest competitors and the UK's top three mobile-telecoms companies. O2 (UK) Telefónica UK Limited (trading as O2 – stylised as O) is a telecommunications services provider in the United Kingdom, owned by the Spanish multinational Telefónica, and is headquartered in Slough. With 25 million subscribers (as of December 2017), O2 is the second-largest mobile network operator in the United Kingdom after EE, with Vodafone in third place. O2 was formed in 1985 as Cellnet, a 60:40 joint venture between BT Group and Securicor. In 1999, BT Group acquired
Institute of Science and Technology, UK Institute of Science and Technology, UK The Institute of Science and Technology is a UK-based professional organization which is a member of the Science Council and thereby authorized to award the designation Registered Science Technician (RSciTech), Registered Scientist (RSci) and Chartered Scientist (CSci). It was formed in 1948 as the Science Technology Association, became the Institute of Science Technology (IST)in 1954 and took its present name in 2007. The IST was formed specifically for science laboratory technicians, and continues to provide specialist qualifications in this area, up to Higher Diploma but has expanded the membership in line with developments in