IEnumerable vs IQueryable

IEnumerable<Employee> emp = ent.Employees;

IEnumerable<Employee> temp = emp.Where(x => x.Empid == 2).ToList<Employee>();

IQueryable<Employee> emp = ent.Employees;

IEnumerable<Employee> temp = emp.Where(x => x.Empid == 2).ToList<Employee>();

Fonte: http://www.codeproject.com/Articles/766541/IEnumerable-vs-IQueryable