Short answers, pulled from the story.
It comes from two Ancient Greek words, philos and sophia, combining affection or love with wisdom. Some sources credit the pre-Socratic thinker Pythagoras with coining the term, though that is not certain. The word entered English around 1175 CE through Old French and Anglo-Norman, carried in from the Latin philosophia.
Epistemology, ethics, logic, and metaphysics are often listed as the main branches. Epistemology studies knowledge, ethics studies right conduct, logic studies correct reasoning, and metaphysics studies the most general features of reality. Other subfields include aesthetics, philosophy of language, philosophy of mind, philosophy of religion, philosophy of science, and political philosophy, and the divisions are neither exhaustive nor mutually exclusive.
Before the modern age the term philosophy was used in a wide sense that included most forms of rational inquiry. Natural philosophy was a major branch that covered physics, chemistry, and biology. Isaac Newton's 1687 book Philosophiae Naturalis Principia Mathematica used natural philosophy in its title but is considered a book of physics today. The meaning narrowed toward the end of the modern period to focus on metaphysics, epistemology, and ethics.
The influential traditions are Western, Arabic-Persian, Indian, and Chinese philosophy. Western philosophy originated in Ancient Greece in the 6th century BCE. Arabic-Persian philosophy arose in the early 9th century CE and centers on the relation between reason and revelation. Indian philosophy combines the spiritual question of enlightenment with the nature of reality and knowledge. Chinese philosophy focuses on right social conduct, government, and self-cultivation. Other traditions include Japanese, Latin American, and African philosophy.
Philosophers use conceptual analysis, reliance on common sense and intuitions, thought experiments, analysis of ordinary language, description of experience, and critical questioning. These often differ from the natural sciences because they do not rely on experimental data from measuring equipment. Approaches include reflective equilibrium, the pragmatic method of Charles Sanders Peirce, phenomenological bracketing or epoche associated with Edmund Husserl, and methodological naturalism, which emphasizes the empirical methods of the natural sciences.