Laissez-faire Economics: This refers to an economic policy of letting owners of industry and business set working conditions without interference from government. It's like letting kids decide their own bedtime - they're free to do what they think is best for them.
Trickle-down Theory: This is an economic theory that advocates reducing taxes on businesses and the wealthy in society as a means to stimulate business investment in the short term and benefit society at large in the long term. Imagine pouring water at the top of a hill (the wealthy) - eventually, it'll trickle down to reach all parts at bottom too (the rest of society).
Reaganomics: Named after Ronald Reagan, this refers to economic policies promoted by U.S. President Ronald Reagan during 1980s, which called for widespread tax cuts, decreased social spending, increased military spending, and deregulation of domestic markets.