--- title: "Vocabulary: historical thinking" description: "Know and use the vocabulary of historical thinking: source, evidence, primary source, secondary source, artefact, chronology, chronological order, BC/BCE, AD/CE, century, decade, era, period, timeline" canonical: https://lightmysky.com/learn/history/vocabulary-historical-thinking-mt_VXcua6-txq source: https://lightmysky.com/learn/history/vocabulary-historical-thinking-mt_VXcua6-txq.md retrieved: 2026-10-19 --- > **Agent view.** This is the Markdown twin of the page, for tools and assistants. > When to use this site, and the call that answers each job: https://lightmysky.com/agent-instructions.md > API description (OpenAPI 3.1): https://lightmysky.com/openapi.json · Authentication: https://lightmysky.com/auth.md > Pricing: https://lightmysky.com/pricing.md · Catalog: https://lightmysky.com/llms.txt · Full catalog: https://lightmysky.com/llms-full.txt > Every machine-readable file on this domain: https://lightmysky.com/.well-known/ai-catalog.json > Ask for Markdown with `Accept: text/markdown`, a `.md` address, or `?mode=agent`. # Vocabulary: historical thinking Know and use the vocabulary of historical thinking: source, evidence, primary source, secondary source, artefact, chronology, chronological order, BC/BCE, AD/CE, century, decade, era, period, timeline, excavation, archaeologist, interpretation, corroborate, bias, perspective. Apply these terms when discussing how we know about the past and how reliable our knowledge is. Subject: History · Area: Historical Thinking · Ages 6 to 10 Page: https://lightmysky.com/learn/history/vocabulary-historical-thinking-mt_VXcua6-txq ## Ready when they can - Correctly use BC/BCE and AD/CE to place events in time and explain what the letters stand for - Distinguish between a primary source and a secondary source with an example of each - Use 'evidence', 'interpretation', and 'bias' correctly in a sentence about a historical source ## Lesson: Words for finding out about the past BC means Before Christ. BCE means Before Common Era. They name the same years. BC numbers get smaller as time moves forward: 30 BC came before 20 BC. BC events came before AD events. Check the labels before comparing numbers. AD means Anno Domini. CE means Common Era. They name the same years, including year 1. The year after 1 BC or BCE is AD 1 or 1 CE. There is no year zero. *(drawing: These years come one after another. AD/CE includes year 1. There is no year zero.)* A decade lasts 10 years. A century lasts 100 years, such as the stretch from 1700 to 1800. A period or era is a named stretch whose length can vary. A timeline puts events in chronological order, from earlier to later. Use dates and clues such as before and after. A source gives clues about the past. A primary source is an original record or object from the time you study, or a firsthand account of what someone experienced themselves. A photo taken at an event is primary for that event. The date when an old object was found does not change when it was made. Check its time and place. A secondary source explains or compares other sources. A website explaining old school lists is secondary for that school's past. Pictures of the original lists still show primary sources. Someone's own memory can be primary even if written down later. Ask what the source does, not just how old it is. Evidence means clues we use to answer a question. Letters, pictures and objects may give clues. One old shoe may help us study shoes, but cannot tell us exactly how everyone lived. Ask whether the clues are enough for the story. An interpretation explains what clues may mean. Burnt roof beams are clues; saying a building may have burned is an interpretation. Fish bones in a bowl may suggest a meal, but do not tell us exactly how they got there. Separate the find from the idea, then check the explanation. Bias means leaning toward one side in how a story is told. Praising successes while hiding known problems can show bias. Having your own view does not prove bias. A ruler's praise for a rule does not show everyone's views or the ruler's private thoughts. Check other accounts. Perspective means a person's point of view. Two people can feel differently about one event. Stories may also differ because people noticed different things, forgot details, made mistakes or favored a side. A primary source can contain mistakes, leave things out or favor one side. Corroborate means check a source against other clues about the same thing. Ask how each writer knows: did they use their own clues or copy the story? A useful check can be old or new. Compare details before deciding whether they agree. Choosing the newest book is not this check. Artefacts are objects made or changed by people, such as tools, clothes and cups. They need not be costly or found underground. An archaeologist studies things left behind to learn about people. An excavation is a careful dig that records where each find lay. It means the digging work, not the objects found. **Recap.** Use time words carefully. Separate clues from explanations, and check what sources say before deciding. ## Practice 24 questions on this page, each with its working shown. ## Opens up - [Different accounts of the same event](https://lightmysky.com/learn/history/different-accounts-of-the-same-event-mt_2GDBmKCJxs) - [Evidence from the past](https://lightmysky.com/learn/history/evidence-from-the-past-mt_9REmUc8r4D) - [Understanding People in Their Own Time](https://lightmysky.com/learn/history/understanding-people-in-their-own-time-mt_IlyE-Sm8k5) - [Evidence versus interpretation](https://lightmysky.com/learn/history/evidence-versus-interpretation-mt_Lu4H4mbsqO) - [Checking sources against each other](https://lightmysky.com/learn/history/checking-sources-against-each-other-mt_wWlZoLQBR6) - [Domain Vocabulary Across Subject Areas](https://lightmysky.com/learn/english/domain-vocabulary-across-subject-areas-mt_WzOyJFKDIu)