Answer:
civil services is not only a service is a vast group of services. under it ias, pcs, ifs,etc.. type services comes.you have to clear the toughest examination to be a part of civil service.
ias ranked people can send throughout the country whereas a pcs is for state only.these distribution of ias and pcs is totally depended on the ranking system.
for civil service you have a shure vision and for civil services Graduation is must.