title: What do the plus and minus signs mean in Objective-C next to a method?
body: <p>In Objective-C, I would like to know what the <code>+</code> and <code>-</code> signs next to a method definition mean.</p>
  
  <pre><code>- (void)loadPluginsAtPath:(NSString*)pluginPath errors:(NSArray **)errors;
  </code></pre>