function setCookie(name, value, expires, path, domain, secure) {
    var curCookie = name + "=" + escape(value) +
      ((expires) ? "; expires=" + expires.toGMTString() : "") +
      ((path) ? "; path=" + path : "") +
      ((domain) ? "; domain=" + domain : "") +
      ((secure) ? "; secure" : "");
    document.cookie = curCookie;
  }

• name - name of the cookie
• value - value of the cookie
• [expires] - expiration date of the cookie (defaults to end of current session)
• [path] - path for which the cookie is valid (defaults to path of calling document)
• [domain] - domain for which the cookie is valid (defaults to domain of calling document)
• [secure] - Boolean value indicating if the cookie transmission requires a secure transmission
• * an argument defaults when it is assigned null as a placeholder
• * a null placeholder is not required for trailing omitted arguments

Notice how we check for argument existence. For example:

  ((expires) ? "; expires=" + expires.toGMTString() : "")

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