Lessons

Introduction
• SEO
  • Broken links
    CSS files are not available for download Images are not available for download JavaScript files are not available for download Broken links Beautiful page 404
  • Site map
    The content of the site map The site map file
  • Semantic markup
    Semantic markup format requirements and recommendations Validation of semantic markup Yandex and Google
  • Robots.txt
    Content robots.txt Errors in Robots.txt
  • References
    The page links to itself. Cyclic references. The "title" attribute of links Link to the main page of the site Human-friendly link format Link format requirements
  • Text
    Rules for formatting text on a page Spelling errors in the title or meta tags Spelling of interactive interface elements
  • Duplicates
    Duplicate "title" Duplicate "description"
  • Basic
    Headings H1-H6 The "description" meta tag Title tag hreflang tag "canonical" tag Content of the Title Title Brand name in the Title header
  • Pictures
    Images have the "alt" attribute. Human-understandable name of the picture
• Speed
  • Minification
    Minification of CSS to reduce its volume Minification of the embedded JavaScript code of the page Minification of the embedded CSS code of the page Minification of images without loss of quality Minification of JavaScript files to reduce its volume Unused CSS code Data optimization:Image URLs Animated image format MP4, WEBM, SVG instead of GIF and WEBP Unused JavaScript code Using the WebP format in images Too high-quality images without using compression Suitable video bitrate
  • Reducing requests
    An overabundance of small pictures Grouping CSS files Grouping JavaScript files An overabundance of font files Availability of end-to-end CSS, JS files The presence of a monochrome font Uploading duplicate files Using JavaScript facades Redirecting JavaScript code Adding lazy loading Redirect from/to www version
  • Fonts
    Specifying default fonts Font Optimization An overabundance of monochrome icons
  • Loading time
    Acceptable size of the HTML code of the page HTML code generation time The total size of all images on the page Page load time Total page load time. Display time of the first graphic Optimal time to download files from the server Time to download files from the server under load Blocking files
  • Server Settings
    304 response code when checking the operation of caching ETag header for caching operation The "Expires" header for caching to work Server GZip compression function Title "Keep alive" Redirects when uploading files Using the modern HTTP2 protocol to speed up the site
  • Pictures
    The original size of the image and the size of its display area Using sprite technology Recompressed images with artifacts Cropping monophonic fields in images
  • The first content
    The sequence of connecting JavaScript files Font display mode Setting up a pre-connection Removing lazy loading Long JavaScript code execution time File upload delayed or on demand The server is located in the same country where the users of the site live No requests to another country that cause page loading to be blocked
• Mobility
  • Screen support
    Adapting the layout to a Full HD computer monitor Adapting the layout for a horizontal tablet Adapting the layout for a horizontal phone Screenshots for the mini-report How blocks break the page layout Adapting the layout to an HD computer monitor Adapting the layout for a vertical tablet Adapting the layout for a vertical phone
  • Comfort
    Finger friendly
• Bugs
  • Code
    JavaScript error messages in the browser console HTML Validation Validation of CSS code The video player is connected correctly
  • Availability
    AAAA DNS server record IPv6 connection
  • Server
    Configuring HTTP Headers Erroneous extension of images Corrupted files Matching the Mime Type to the file
• Convenience
  • Social networks
    Snippets of the site when sending links in social networks and instant messengers
  • Web Application Manifest
    Manifest validation.json with a list of favicons
  • Favicons
    Splitting the page into HTML5 sections List of scanned links Tag for specifying a large favicon The BrowserConfig file Apple touch bar icon for Mackbook pro Favicon.ico file
  • Mail
    SPF DNS server record DMARK DNS server record MX record of the DNS server Reverse DNS record
  • Basic
    Phones without a clickable link to start a call quickly Links for Email addresses Background image flickering on hover Interface responsiveness Annoying pop-up messages without the user's knowledge Images when loading cause a sharp change in the structure of the page
  • Text readability
    Sufficient text contrast Readable text size Line spacing of the text The size of the text in the pictures
• Vulnerabilities
  • Encrypted connection
    Encrypted IPv6 connection SSL certificate validity HTTPS Availability Redirects to protected
  • Exploits
    Uploading all page files via HTTPS CSFR protection of HTML forms The header is "Strict HTTPS" to increase security Using Java applets Private access to service files Enabled error display in the north HTTP headers for increased security
  • Vulnerabilities
    Vulnerable JavaScript code Vulnerable JavaScript libraries Antiviruses Vulnerabilities of a secure SSL connection