Although meditation as a practice is incredibly simple, it’s crazily difficult to define. In the West, to meditate might mean to think deeply about a specific subject. In the East, on the other hand, it’s more likely to mean a process of distancing yourself from your thoughts and silencing your mind.
This video from the School of Life explains it pretty well. This page is mostly aimed at resources for the Eastern style of meditation — silencing your mind.
Where I stand
More important (in my eyes at least) than any definition is the practical benefits of practising meditation. My experience has been that meditation has allowed me to slow down my mind, escaping from the hectic racing of thoughts that used to fill it. Once my mind began to feel a little less crammed full, I felt far better able to think clearly and focus on the present moment. Over time I’ve become better at recognising my own mental habits (good and bad), learning how modify them to remove negative patterns of thought (stuff like excessive self-doubt). In short, it’s allowed me to take back control of my mind.
Where to start
Above you’ll have seen a range of resources related to meditation. These are all useful and starting with any of them has the potential to create a spark of interest that you can pursue further. However, I would recommend starting with one specific resource as it’s a great introduction to meditation — Silence Your Mind by Ramesh Manocha.