Plain-language explanation.
Political science studies power — how it is distributed, exercised, and contested in societies. It examines governments, elections, political parties, public policy, constitutions, and international order. Political scientists seek to understand both what politics is and what it should be.
Core concepts and standard treatment.
Core political science covers political concepts: power (Dahl — A exercises power over B by getting B to do something B would not otherwise do; Lukes — three dimensions of power — decision-making, non-decision-making, shaping preferences; Foucault — dispersed productive power); legitimacy (Weber — traditional, charismatic, rational-legal authority; political obligation; consent of the governed — Locke), the state (Weber's definition — monopoly on legitimate use of force; Schmitt — the political — friend/enemy distinction; failed states — FSI; welfare state — Esping-Andersen — three worlds of welfare capitalism), and democratic theory (majority rule vs minority rights; pluralism — Dahl 'Who Governs?'; elitism — C. Wright Mills — 'The Power Elite'; deliberative democracy — Habermas; participatory democracy; democracy indices — V-Dem, Freedom House, EIU Democracy Index).
Deeper theory, debates and edge cases.
Advanced political science covers comparative politics (most similar / most different systems design — MSSD/MDSD; institutionalism — historical, rational choice, sociological; Hall and Taylor; Lijphart — 'Patterns of Democracy' — majoritarian vs consensus democracy; Lijphart's 36 democracies; Arend Lijphart — consociational democracy; Veto players — Tsebelis; varieties of capitalism — Hall and Soskice — liberal vs coordinated market economies), public policy analysis (policy cycle — agenda setting, formulation, decision, implementation, evaluation; Kingdon — multiple streams — problem, policy, political streams — policy windows; Sabatier — advocacy coalition framework; Baumgartner and Jones — punctuated equilibrium; nudge and behavioural public policy), and populism and democracy backsliding (Mudde and Kaltwasser — populism as thin ideology — people vs corrupt elite; Levitsky and Ziblatt — 'How Democracies Die' — backsliding via legal means — Hungary, Turkey, US January 6; V-Dem backsliding indicators; Cas Mudde — four faces of right-wing populism).
How it is applied in practice.
At the professor, special adviser, think-tank analyst, and civil servant level, practitioners contribute to American Political Science Review and Political Studies; advise ministers and parliamentary committees (SPADS — Special Political Advisers; Select Committee specialist advisers; House of Commons Library political analysis); contribute to political party research and strategy (polling — YouGov, Ipsos MORI, BMG; electoral modelling — Electoral Calculus; message testing — focus groups; Voter ID legislation impact analysis); conduct policy evaluation (National Audit Office — VFM studies; What Works Centres — NICE, EEF, What Works Centre for Wellbeing; Magenta Book — HMT evaluation guidance); and work in international electoral democracy support (International IDEA — democracy assessment; NDI, IRI — US democracy assistance; Carter Center — election observation; OSCE/ODIHR — election monitoring — long-term and short-term observer missions).