title: preg_match in php
body: <p>I want to use <code>preg_match()</code> such that there should not be special characters such as ``@#$%^&amp;/ '` in a given string.</p>
  
  <p>For example :</p>
  
  <p><code>Coding</code> : Outputs valid<br>
  <code></code>: Outputs Invalid(String beginning with space)<br>
  <code>Project management</code> :Outputs valid (space between two words are valid)<br>
  'Design23' :Outputs valid<br>
  <code>23Designing</code> : outputs invalid<br>
  <code>123</code> :Outputs invalid<br></p>
  
  <p>I tried but could not reach to a valid answer.</p>