As I said in a previous blog-post, there’s a number of different definitions that people use for philosophy. I generally settle for “examining the nature of knowledge, existence and what is real”. It originates from the Greek word philosophia, which means “the love of wisdom”.

Here's a few examples of some 'branches' within philosophy:

Aesthetics – the study of the characteristics of beauty and taste, especially in art. It originates from the Greek word aisthetikos (from aisthesthai), meaning “perspective”. Essentially we’re looking at what we know and agree upon (and debate about!) when it comes to the characteristics of art, what makes good art, and what perspectives people have and why.
Epistemology – the study of knowledge, especially the scope of knowledge. It originates from the Greek word episteme, which means “knowledge”. This includes how we gain knowledge of things (and how we justify claims in that vein).
Ethics – the study of what is morally right. It originates from the Greek word ethos, which means “character”. When studying ethics, we’re looking at what is right and wrong, how we justify particular ethical stances on issues and why.
Logic and the Philosophy of Language – the study of logical thought, rationality, reasoning and arguments. It originates from the Greek word logikē, relating to “reason”. 
Metaphysics – the study of the fundamental nature of existence, being and the world, looking at what is real. Origin from the Greek ta meta ta phusika: “the things after the physics”.

Arguably there’s other branches in philosophy, such as educational philosophy, political philosophy and so on, but there are some of the aspects that will arise again and again over the rest of the series throughout this year. Big credits to the Oxford Dictionary and Thesaurus for help with the Greek definitions.