12 best websites for tracing British First World War soldiers

These recommendations from Who Do You Think You Are? magazine are worth a look  -- www.whodoyouthinkyouaremagazine.com/12-best-websites-tracing-british-first-world-war-soldiers.
Some of the websites are also good for Canadians, just add in the Canadian Virtual War Memorial, resources at Library and Archives Canada, and Canada and the First World War from the Canadian War Museum as background.