  The ability of spintronic devices to utilize an electric current for
manipulating the magnetization has resulted in large-scale developments, such
as, magnetic random access memories and boosted the spintronic research area.
In this regard, over the last decade, magnetization manipulation using
spin-orbit torque has been devoted a lot of research attention as it shows a
great promise for future ultrafast and power efficient magnetic memories. In
this review, we summarize the latest advancements in spin-orbit torque research
and highlight some of the technical challenges for practical spin-orbit torque
devices. We will first introduce the basic concepts and highlight the latest
material choices for spin-orbit torque devices. Then, we will summarize the
important advancements in the study of magnetization switching dynamics using
spin-orbit torque, which are important from scientific as well as technological
aspect. The final major section focuses on the concept of external assist field
free spin-orbit torque switching which is a requirement for practical
spin-orbit torque devices.
