What does Google say about SEO? /
This category compiles all official Google statements regarding the processing and indexing of non-HTML file formats, including PDF documents, Flash files (SWF), and XML documents. Optimizing these file types represents a critical challenge for SEO professionals managing websites with extensive technical documentation, reports, catalogs, or structured content. Google's ability to crawl and index these resources has evolved significantly over the years, making it essential to understand their official recommendations. PDF files receive special treatment in search results, with specific implications for optimization, markup, and accessibility. Legacy technologies like Flash have been progressively deprecated, while structured formats such as XML play a vital role in search engine communication through sitemaps. This section aggregates Google's official positions on optimization best practices, technical limitations, recommended alternatives, and indexing strategies for each file type. Whether you're dealing with document repositories, legacy content migration, or structured data implementation, these official declarations provide authoritative guidance for handling alternative content formats. An invaluable resource for any SEO practitioner facing the challenges of optimizing and ranking non-HTML content in Google search results.
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★★★ Does loading JavaScript from too many domains really slow down your site's first impression?
If JavaScript files are loaded from different domain names, there can be a DNS lookup overhead per domain. An excessive number can slow down a user's first visit to your site....
Alan Kent May 17, 2022
★★★ Is excessive JavaScript fragmentation killing your SEO performance?
The number of JavaScript files can increase rapidly if each UI component lives in a separate file. There are overheads per downloaded file, especially for sites using HTTP/1. It is recommended to cons...
Alan Kent May 17, 2022
★★★ Should you really compress all your JavaScript files to boost your SEO performance?
JavaScript files typically compress well, reducing the bytes that need to be downloaded. Although the browser uses more CPU to decompress, compression is normally beneficial overall. PageSpeed Insight...
Alan Kent May 17, 2022
★★ Is HTTP/2 making JavaScript file concatenation obsolete for SEO?
HTTP/2 support on your site can improve performance without requiring you to join files, since HTTP/2 enhances the efficiency of downloading multiple small files....
Alan Kent May 17, 2022
★★★ Should you really keep the 'priority' tag in your sitemaps?
Google does not use the 'priority' tag in sitemap files. This information is explicitly mentioned in Google's official documentation. Website owners tend to mark all their pages as priority, making th...
John Mueller May 05, 2022
★★ Should you still bother filling in the lastmod tag in your XML sitemaps?
Unlike Google, Bing uses the 'lastmod' tag from sitemap files. Google doesn't use it due to its poor reliability, as sites often update it without any significant content changes....
Gary Illyes May 05, 2022
★★★ Should you really remove the 'changefreq' tag from your sitemaps?
Google does not use the 'changefreq' (change frequency) tag in XML sitemap files. It is impossible for site owners to accurately predict how often a page will actually change, making this information ...
Gary Illyes May 05, 2022
★★ Can Googlebot actually access your .htaccess file?
Googlebot generally cannot access the .htaccess file because servers are configured to block external access. However, Google sees the effects of this file since it controls how the server responds to...
John Mueller Apr 29, 2022
★★ Does Google really read every single piece of user feedback submitted on their documentation?
The Google team reads all user feedback submitted daily via the feedback form on the documentation. Quality feedback that clearly specifies the problem is handled the same day or quickly....
Gary Illyes Apr 26, 2022
★★ Why should you implement generic structured data types before tackling specific ones?
To get started with structured data, you first need to look at generic features that apply to most sites: breadcrumbs, site link search box. Then, verify if there is documentation for specific types r...
Ryan Levering Apr 07, 2022
★★★ Why Can Your Valid Schema.org Markup Get Rejected by Google?
Schema.org is a common vocabulary, not an API. It doesn't specify what is required. Google imposes additional restrictions on Schema.org to make data usable for its specific features. Data can be corr...
Ryan Levering Apr 07, 2022
★★★ Is your cached content being blocked by browser security policies, and how is Google affected?
Due to browser security, there are restrictions on how content can be accessed from a page. For example, if a page requires a JavaScript file from your server, browsers may block this request when it ...
John Mueller Apr 06, 2022
★★★ Should You Really Remove Redirected URLs from Your XML Sitemap?
John Mueller explained on Twitter that when you redirect a URL, you can temporarily leave the original URL in the XML Sitemap (1 to 3 months), giving Google time to discover and process it. While this...
John Mueller Apr 04, 2022
★★ Does the location of your XML sitemap really affect crawl efficiency?
The location of the sitemap file doesn't really matter. You can place it in a subdirectory, subdomain, or different host. If it's listed in your robots.txt file, you can put it anywhere....
John Mueller Mar 28, 2022
★★★ Should you sacrifice traffic volume to reach the right audience?
Changing a page's title and meta description to more precisely target your desired audience can significantly reduce unqualified traffic. In the documented case, organic traffic dropped from 40% to 20...
Lizzi Sassman Mar 24, 2022
★★★ Should you use rel=canonical instead of noindex to handle similar content?
To manage closely related content such as a blog article and a documentation page on the same subject, it is preferable to use the canonical tag rather than noindex. This allows search engines to unde...
Gary Illyes Mar 24, 2022
★★★ Should you really avoid generic keywords in SEO?
Optimizing your site for overly generic queries can attract the wrong type of traffic. Users arriving through these generic queries won't be able to accomplish the desired action because the documenta...
Martin Splitt Mar 24, 2022
★★★ Why are your CSS background images invisible to Google Images?
Images embedded via the CSS 'background-image' attribute are generally not detected for Google Images. Google focuses on the img tag with its src attribute, the picture element, or direct links to ima...
John Mueller Mar 22, 2022
★★★ Can a 500 Error on Your robots.txt Really Block Your Entire Site Crawl?
Still in this hangout, John Mueller indicated that if, when the bot attempts to read a site's robots.txt file, it received a server error (5xx type) via a CDN or not, this resulted in a loss of displa...
John Mueller Mar 21, 2022
★★ Which meta tags does Google actually use for SEO rankings?
Google offers official documentation listing all the meta tags that the search engine uses and understands. It is recommended to consult this resource to know which elements can influence search resul...
John Mueller Mar 15, 2022
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