Usability.gov provides overviews of the user-centered design process and various UX disciplines. It also covers the related information on methodology and tools for making digital content more usable and useful.
A good overview of the UX design process, with links to tools and explanatory videos
Founded by Pabini Gabriel-Petit in 2005, UXmatters provides insights and inspiration to experienced professionals working in every aspect of User Experience, as well as those who are just beginning their journey in the field.
Nielsen Norman Group share their research findings to help designers and teams improve user experiences through various articles and videos related to User Research