title: How to generate short uid like "aX4j9Z" (in JS)
body: <p>For my web application (in JavaScript) I want to generate short guids (for different objects - that are actually different types - strings and arrays of strings)</p>
  
  <p>I want something like "aX4j9Z" for my uids (guids).</p>
  
  <p>So these uids should be lightweight enough for web transfer and js string processing and quite unique for not a huge structure (not more than 10k elements). By saying "quite unique" I mean that after the generation of the uid I could check whether this uid does already exist in the structure and regenerate it if it does.</p>