Basic Conception
Machine learning is a study of how to use experience to improve the performance of systems themselves by computational means.
In computer systems, EXPERIENCE is often in the form of DATA.
The main content of machine learning is about algorithms that generate MODEL from data. We call it a learning algorithm.
Machine learning require data first. Suppose we’ve collected a batch of data about watermelons, for example
(color = light white,root = curled up,tapping = dull)
(color = black, root = slightly curled up, tapping = not crisp) …
The set of records is called a data set.