before HRM, PM(Personnel Management) deals with the employees in organisation, but when human beings considered as a resource which is most important rather than other resouce and who is senstive and naturally possess human right and a life full of dignity, then new concept HRM, a deptt. which is responsible for management of everything regarding human resouce working in a particular organization..one thing which i also came to know that HRM day is celebrated on August 11th every year...
Thanks & regards
Naresh Kumar