Israel is a leading country in the development of solar energy. Israel is a global leader in water conservation and geothermal energy, and its development of cutting-edge technologies in software, communications and the life sciences have evoked comparisons with Silicon Valley. According to the OECD, Israel is also ranked 1st in the world in expenditure on Research and Development (R&D) as a percentage of GDP. Intel and Microsoft built their first overseas research and development centers in Israel, and other high-tech multi-national corporations, such as IBM, Google, Apple, HP, Cisco Systems, and Motorola, have opened R&D facilities in the country.