Qualitative and quantitative reseach?

Quantitative research is generally more related to physics and "measuring" results which can often be expressed as numbers, and are reproducible using the scientific method:
"45% of the people tested prefer product A, 37% prefer product C"
"light travels at 2.997m/s"

Qualitative research is more related to things that cannot be easily measured or proven, such as why people do certain things.