Answer:

Primary Sources

A primary source provides direct or firsthand evidence about an event, object, person, or work of art.  Primary sources provide the original materials on which other research is based and enable students and other researchers to get as close as possible to what actually happened during a particular event or time period.   Published materials can be viewed as primary resources if they come from the time period that is being discussed, and were written or produced by someone with firsthand experience of the event.  Often primary sources reflect the individual viewpoint of a participant or observer.  Primary sources can be written or non-written (sound, pictures, artifacts, etc.).  In scientific research, primary sources present original thinking, report on discoveries, or share new information.

Examples of primary sources:

Autobiographies and memoirs

Diaries, personal letters, and correspondence

Interviews, surveys, and fieldwork

Internet communications on email, blogs, listservs, and newsgroups

Photographs, drawings, and posters

Works of art and literature

Books, magazine and newspaper articles and ads published at the time

Public opinion polls

Speeches and oral histories

Original documents (birth certificates, property deeds, trial transcripts)

Research data, such as census statistics

Official and unofficial records of organizations and government agencies

Artifacts of all kinds, such as tools, coins, clothing, furniture, etc.

Audio recordings, DVDs, and video recordings

Government documents (reports, bills, proclamations, hearings, etc.)

Patents

Technical reports

Scientific journal articles reporting experimental research results

Secondary Sources

Secondary sources describe, discuss, interpret, comment upon, analyze, evaluate, summarize, and process primary sources.  A secondary source is generally one or more steps removed from the event or time period and are written or produced after the fact with the benefit of hindsight.  Secondary sources often lack the freshness and immediacy of the original material.  On occasion, secondary sources will collect, organize, and repackage primary source information to increase usability and speed of delivery, such as an online encyclopedia.  Like primary sources, secondary materials can be written or non-written (sound, pictures, movies, etc.).  

Examples of secondary sources:

Bibliographies

Biographical works

Reference books, including dictionaries, encyclopedias, and atlases

Articles from magazines, journals, and newspapers after the event

Literature reviews and review articles (e.g., movie reviews, book reviews)

History books and other popular or scholarly books

Works of criticism and interpretation

Commentaries and treatises

Textbooks

Indexes and abstracts