What is difference between HR and admin?

Human Resources manage all Employee and Employee Related Matters (Recruitments, Induction, Payroll, Perfromance management, Hr Policies, Exit Management, etc) that affect Productivity in an Organization.
  Administration relates to all matters related to Office Management - Travel Arrangments, Infrastructure management, etc..

HR deals with only the Human resource(Employer & Employees) activities i.e. Recruting, Compensation & benefits, Employee relationship, Training & Development, Health & Saftely, Record keeping & Payroll etc.  

While 

Administration deals with general administrative responisbilities i,e, clerical, Data Entry, secreterial and office Management, taking care of the support activites

HR is the specialized field dealing with HUMAN resources / aspect of the organization and ensuring that Human resources are providing competative advantage to organization and as per mission, whereas, Administration deals with policies, proceedures, rules regulations, maintenance of office buildings, discipline, arrangement of transportation  and make sure that every day requirements of organization are met.

Human Resources manage all Employees and Employee Related Matters Means Inside office Administration relates to all matters related to Office Management    Means inside & outside office (office related work ,electricity ,municipality & chamber of commerce

Administration make and imply policy for all department about discipline and make sure the every department in surving in the right path to meet organization's mission, whereas, HR is the specialized field to finds out the talented employee from job market, uplift their productivity and motivate them as a supporting hand to the organization.