Regardless of complexity or price tag, every website should include all of the following items:

• What You Do/Who You Are: This may seem a little obvious, but in the fury of building a site and doing lots of "marketing" and "promoting" and "search engine optimizing", some websites skip this ever important detail. This important task doesn't have to be accomplished with a 1,000 word essay. You can use images or videos to communicate what it is you do and who you serve. Just make sure your purpose gets communicated somewhere on your website.
• Contact Information: This is so important! Having easy to access contact information like phone numbers, email addresses, mailing addresses and social network links can really make or break a visitor's time on your website. If this information isn't immediately available on your home page, or isn't available after just one click, an update is probably in order.
• Simple Navigation: Your website should be super easy to navigate. This means usually including one main menu that can help visitors find the information they need fast. The two pitfalls to watch out for here include having too many menus and having no menu at all (or having a menu that is difficult to find, which is basically the same thing as having no menu). Both are problems. A well designed site should have one central menu that serves as the backbone of the site. Beware of overly packed menus too... these often hinder more than they help. This is especially true for dropdown menus with more than 2 levels of depth. If your navigation menu has this many links... I'd recommend changing up the format of your main menu, or adding in some side menus.
• Graceful Failure: Websites don't always work. Sometimes links are incorrect. Sometimes your browser doesn't understand the underlying code of your site well enough to make it look correct (I'm looking at you Internet Explorer). Your website shouldn't grind to a complete hault just because one piece of the site fails. Bad links should lead to a helpful 404 page. Websites that aren't compatible with your browser should still be easily readable and reasonably clean even in older browsers.
• Mobile Layout/Responsive Design: In 2013, nearly 30% of all web traffic came from mobile devices. That means 1/3 of your website visitors are potentially using a smart phone or tablet. Your website should be easily accessible on their smaller screens. In the olden days of five years ago, completely separate mobile websites were the answer to this conundrum. Today, the best way to achieve this mobile-friendly strategy is via responsive design. With responsive design, clients only need to manage one site, but the site will automatically rearrange itself to fit into a smaller space. Even if your site isn't ready for responsive design quite yet, make sure that your menus are navigable with taps (instead of clicks) and your overall website file size remains as small as possible. Full Disclosure: THIS site still needs the responsive treatment. It's hopefully coming very soon!
• Social Connections: People use the internet in vastly different ways. While some prefer to check out your organization's website, others may go looking for a Facebook page first, or maybe an Instagram account, or possible a Twitter account. If you aren't represented in these areas, your business is probably losing out. Invest just a little bit of time in your social network connections. On a related note, most websites should have a way to easily share their information to social networks. Adding in widgets like the "Add This" bar is a simple, easy way to let visitors spread the word on your organization for you.

These are the basics, but I'm sure I missed some. What else should go in the "Must Have" website list?