I recently bought a tiny house since there isn't much space in my city for a big house!
Oh that's cool! It's a whole movement. It advocates living simply in small homes but you know that
I agree, its a movement so save space and protect the environment. 
There currently no set definition as to what size a tiny house is. 
Yea I bet it varies from place to place. What else do you about tiny houses?
then Four Lights Tiny House Company (September 6, 2012). In 2002, Shafer co-founded, along with Greg Johnson, Shay Salomon and Nigel Valdez the Small House Society. Salomon and Valdez subsequently published their guide to the modern Small House Movement, "Little House on a Small Planet" (2006) and Johnson published his memoir, "Put Your Life on a Diet" (2008).
With the depression hitting in 2008, the small house movement attracted more attention as it offered affordable, ecologically
Tiny house movement
The tiny-house movement (also known as the "small-house movement") is an architectural and social movement that advocates living simply in small homes. there is no set definition as to what constitutes a tiny house. However, a residential structure under 400 sq. ft is generally considered a tiny home. The tiny-house movement promotes financial prudence, economically safe, shared community experiences, and a shift in consumerism-driven mindsets.
Background.
In the United States of America