What is Margaret Thatcher?
{{more sources|date=December 2020}} {{Infobox {{text|prime minister}} | honorific_prefix = {{Pre-nominal styles|RHon|size=100%}} | name = The Baroness Thatcher | honorific_suffix = {{Post-nominals|country=GBR|size=100%|LG|OM|DStJ|PC|FRS|HonFRSC}} | image = Baroness Thatcher in 2005.jpg | alt = portrait of Margaret Thatcher | caption = Portrait of former Prime Minister Margaret Thatcher (2005) | office = [[Prime Minister of the United Kingdom]] | term_start = 4 May 1979 | term_end = 28 November 1990 | monarch = [[Elizabeth II]] <!-- Whitelaw did not hold the title of Deputy PM. See Hennessy (2001, p. 405) -->| deputy = [[Geoffrey Howe|Sir Geoffrey Howe]] {{nowrap|(1989–90)}} | predecessor = [[James Callaghan]] | successor = [[John Major]] | office1 = [[Leader of the Opposition (United Kingdom)|Leader of the Opposition]] | term_start1 = 11 February 1975 | term_end1 = 4 May 1979 | monarch1 = [[Elizabeth II]] | primeminister1 = {{Unbulleted list |[[Harold Wilson]] |[[James Callaghan]]}} | predecessor1 = [[Edward Heath]] | successor1 = [[James Callaghan]] | office2 = [[Leader of the Conservative Party (UK)|Leader of the Conservative Party]] | term_start2 = 11 February 1975 | term_end2 = 27 November 1990 | deputy2 = [[William Whitelaw, 1st Viscount Whitelaw|The Viscount Whitelaw]] | predecessor2 = [[Edward Heath]] | successor2 = [[John Major]] | module = {{Collapsed infobox section begin |Ministerial offices |titlestyle=border:1px dashed lightgrey;}} {{Infobox officeholder |embed=yes |office3 = [[Secretary of State for Education|Secretary of State<br />for Education and Science]] |term_start3 = 20 June 1970 |term_end3 = 4 March 1974 |primeminister3 = [[Edward Heath]] |predecessor3 = [[Edward Short, Baron Glenamara|Edward Shor