A district is an administrative division of a state. Each district in India has an officer-in-charge who represents the state governments in that area in the capacity of Collector/District Magistrate. The office of the collector, is the chief representative of government in a District. District Collectors are entrusted with a wide range of duties in the jurisdiction of the district, which generally involve :

As District Magistrate

Maintenance of law and order.
Supervision of the police and jails.
Supervision of subordinate Executive Magistracy.
Hearing cases under the preventive section of the Criminal Procedure Code.
Supervision of jails and certification of execution of capital sentences.
Arbitrator of land acquisition.
Disaster management during natural calamities such as floods, famines or epidemics.
Crisis management during riots or external aggression.

As Collector

Land assessment
Land acquisition
Collection of excise duties, irrigation dues etc.
Distribution of agricultural loans
Chairman of the District Bankers Coordination Committee
Head of the District Industries Centre

As Deputy Commissioner/District Commissioner

Reports to Divisional Commissioner on all matters.

As District Election Officer

Conducts Elections in the district, be it General, Parliamentary, Assembly or Municipal.
Acts as the Returning Officer for the Parliamentary Constituency in the district.
Collectorate is the hub of all the activities of the government in the district. The Collector, also known as District Magistrate, has wide magisterial and executive powers and manifold responsibilities. In many ways, he is the chief custodian of law and authority, the pivot on which runs the local administration. The Collector, is assisted by Additional District Collectors/Magistrates and Deputy Collectors. Works of office of Collector is divided into different sections. In each section one or two employees are posted who work under the supervision of office superintendent/assistant office superintendent.

In Agra, the District Magistrate/Collector is assisted by seven Additional District Magistrates

Finance and Revenue
Enforcement and Administration
Civil Supply
Land Acquisition
ADM City, several ACM and SDMs.

The Additional District Magistrates, report to the District Magistrate/Collector for all matters under their purview or the responsibility assigned by the Collector.

The Deputy Collectors report to the ADMs, and also, directly to the Collector in matters assigned to them independently. The Deputy Collectors are also posted in Tehsil as SDM (Sub Divisional Magistrate) and reporting to District Magistrate/Collector.

The Collectorate is composed of a series of sections dealing with a varied nature of activities.

Chief Revenue Account (CRA) Section – Revenue related
Nazarat Section – Housekeeping related
Revenue Record Keeper (RRK) Section – Revenue Record related
Judicial Record Keeper (JRK) Section – Judicial Record related
English Record Keeper (ERK) Section – Mail receiving and despatch section
Combined Office Section – Hub of multiple activities
Mining Section – Mining related
Arms Section – Arms and Ammunition Licensing related
Food Safety and Drug Control Section – Food and Drug licensing related
Disaster Section – Disaster Management cell
e-District Section – e-Governance related
Form Keeper Section – Various Forms and stationery related
Sahukari Section – Licensing Money lending related
All the above sections are staffed with sectional heads, senior clerks, clerks, account clerks, computer operators, copyist, electrician, gardeners, multi-tasking persons/peon and watchmen