History

Primary vs secondary sources

A primary source comes from the time itself (a letter, a photograph, a treaty); a secondary source interprets it later (a textbook, a documentary). Strong arguments cite primary evidence and use secondary work for context.

Causes come in layers

Big events rarely have one cause. Historians separate long-term conditions (rivalries, economics), short-term causes (crises, decisions) and triggers (the single spark) — World War I is the classic example of all three.

A thesis is a claim, not a topic

"The Industrial Revolution" is a topic. "The Industrial Revolution raised living standards only after 1850" is a thesis — something specific that evidence could support or challenge.