> as <code>character</code>). Some others are stored as <code>NA</code> representing <em>unknown, not available values</em> (e.g. <code>"ggplot"</code> as <code>numeric</code> or <code>1</code> as <code>logical</code>). Conversion between different data types is very useful but be careful and always inspect the output of the conversion for potential coercion mistakes.</p>
<p>Another important data type is the <code>Date</code> class. Dates are either represented as the number of days since a specified orig