Indian Constitution: Features, Rights, Duties, Directive Principles
Features
Written, largely rigid, federal with a strong centre, parliamentary, republican, with an independent judiciary and judicial review, universal adult franchise, single citizenship, and a blend of rigidity and flexibility in amendment (Article 368). The Preamble declares sovereignty, socialism, secularism, democracy, republic, and the objectives of justice, liberty, equality and fraternity.
Fundamental Rights (Part III)
Enforceable against the state; include equality (Arts 14-18), freedom (19), life and personal liberty (21), freedom of religion (25-28), cultural and educational rights (29-30), and constitutional remedies (32). They are not absolute: reasonable restrictions apply, and Art 32 makes the Supreme Court the guarantor of rights. Rights can be amended but not so as to destroy the basic structure.
Fundamental Duties (Part IVA, Art 51A)
Non-justiciable moral obligations added by the 42nd Amendment.
Directive Principles (Part IV, Arts 36-51)
Non-justiciable goals for a welfare state: livelihood, equal pay, health, education, village panchayats, uniform civil code, environment. They guide policy and are used in interpretation; the balance between Parts III and IV is a recurring theme.
Traps
Do not say DPSPs are enforceable; they are not. Do not confuse Art 32 (Supreme Court writs) with Art 226 (High Court writs). Do not claim Fundamental Rights are absolute. Do not attribute the basic structure doctrine to the Constitution's text - it is judicially evolved.
Rule of thumb
Part III = courts; Part IV = policy; Part IVA = civic duty. That mapping answers most classification questions.
Worked example: A law denying equal pay for equal work may be tested both against Art 14/15 (enforceable right) and Art 39(d) (a Directive Principle guiding interpretation).