I guess everyone has his own vocabulary, the words and phrases he uses to express and explain himself and the world around him. A writer should be especially aware of this; after all, language and its levels of usage and meaning are the tools of his trade. I recently found reason to inspect and evaluate mine.
I find the most common of the words I use are those exchanged in everyday conversation, the nickel-and-dime stuff that gets me through my daily activities. They tend to be simple and direct. They also constitute only a small segment of my personal word-hoard, the common coinage of common transactions.
In contrast, the largest part of my word-hoard or vocabulary consists of the words I read and hear. The words I hear daily are closer to my own everyday language, but there are also words and phrases I hear in the broadcast media. Often bits and pieces of this become part of my daily vocabulary. Then, of course, there are the words I read. Because I don't assume that others read the same words and phrases as I do they only seldom become a part of the usual vocabulary. My reading and understanding have given me a wealth of language - languages, because many phrases and expressions in a number of languages not my own have been easy to grasp and assimilate into what I can read.
The most precious of my word-hoard are the words I write. They encompass a much greater part of the vocabulary I have than that which I speak, but also much smaller than the vocabulary I read. These are the words that have worth for me, the ones I carefully share with others but do not let go; they are my personal treasure.
Picture my vocabularies. On the one side is a cup filled with the common coins. On the other side is a huge tub filled with paper bills, cheques, and other instruments of exchange. But in the middle stands a small chest, heavy and well bound.
I have momentarily opened my treasure chest for you. I have written.