With the number of updates Google and the other search engines make to their algorithms, it can be daunting to stay current with best practices for search engine optimization (SEO). Should backlinks still be a priority? What is Google’s Penguin update and how can I stop losing traffic because of it?

But no matter how much search engines change their ranking equations, there are a number of basic SEO mistakes you’ll want to avoid. Here’s a look at the five most common errors and some advice for how you can avoid making them:

Mistake No. 1: Failing to conduct proper keyword research.

The Internet runs on keywords. Websites show up in search engine results only when they’re relevant to keyword queries.

If you’re posting web content based on whatever you feel like writing rather than based on proper keyword research, you might be limiting your opportunities to generate search results traffic. A keyword is a word or series of words that a user enters into a search engine. To research keywords for your industry, use tools such as Google’s free Adwords Keyword Research service to look for search queries that generate an adequate volume of website results without being so competitive that your site won’t rank high in the search results.

Related: How Keyword Research Can Improve Your SEO

Mistake No. 2: Building low-value backlinks.

Although link building can be an important part of online marketing, you won’t want to put quantity ahead of quality. Low-value backlinks — including those from spam websites, irrelevant sites or sites built solely for the purpose of disseminating links — could do damage to your site’s SEO, especially in the wake of the recent Google Penguin update.

Google Penguin is an algorithmic change designed to weed spam sites out of search results. The quality of a site’s backlink profile is one of the key factors believed to play a role in identifying a site as potential spam and penalizing it. Therefore, focus on pursuing links from authority sites in your industry rather than take the easy way out by acquiring low-value links.

Mistake No. 3: Developing sites that can’t be properly indexed.

The listings on search engines’ results pages are pulled directly from their massive indexes of web pages, which are then analyzed according to the latest ranking algorithms.

How do you get into an index in the first place? Your site must be indexed by the search engines’ robot or spider programs, which digest its textual content and store it for potential display in future search queries.

This represents a significant weak spot for many sites. If the search engines’ spiders can’t index your site accurately, you can’t attract the right kind of traffic from searches. A variety of issues can prevent a website from being indexed correctly, but the following are most common:

• Overuse of images. Search engine spiders can’t read text that’s included in images. If you store important elements like your site’s name or headlines in pictures, such information may not be indexed properly.
• Flash animations. Search engines also struggle to digest the information stored in Flash animations, so use them sparingly.
• Javascript and other code elements. These features can provide great functionality, but they can’t be indexed. To prevent indexing problems, format your site’s robot.txt file to display an alternate, text-based version (instead of your Javascript or code elements) to the search engine spiders.

Related: 3 Ways to Stop Losing Traffic from Google’s Penguin Update

Mistake No. 4: Failing to regularly update your site.

Outdated content reduces your site’s perceived value and can lead to fewer return visitors and decreased sales. The search engines care about your content’s freshness, as well. Adding new content to your site exposes it to a wider range of keywords and potentially more search-generated traffic. New postings also can help your site get ranked for search queries that fall under Google’s recent freshness update.

For queries with a timeliness factor, such as the current U.S. presidential race, this algorithmic change places a premium on providing the most recent results and not necessarily those with the most traditional SEO ranking factors in place. Without regular updates, your site obviously won’t qualify for inclusion in such results.

Mistake No. 5: Focusing on search engines instead of your visitors.

While search engine optimization is important, your visitors matter most. Your SEO activities shouldn’t undermine the quality of your content to the point that readers no longer want to stick around and engage with your site.

Follow established SEO guidelines where you can, but keep the focus on providing value to the people who actually arrive on your site. Make their satisfaction your ultimate priority, and you’ll likely be rewarded with both high search rankings and increased revenues.