Guides — murattunalı.

Accessibility.

17 PAGES · PILLAR: WEB ACCESSIBILITY

01 Web accessibilityCLUSTER PILLAR Web accessibility means a website can also be used by people with visual, hearing, motor or cognitive differences. 02 What is WCAG 2.2 WCAG 2.2 is the web accessibility guideline the W3C published on 5 October 2023, and it is the version referenced today in most countries, Türkiye included. 03 The Presidential Circular and the Ministry checklist The Turkish Presidential Circular dated 24 June 2025 references WCAG 2.2 level A for the websites and mobile applications of public institutions. 04 The difference between A, AA and AAA WCAG’s three conformance levels are an ordering of scope, not difficulty: a site conforming to AA also conforms to A, because the levels stack on one another. 05 How to calculate the contrast ratio The contrast ratio is the ratio of the relative luminances of two colors, taking a value between 1:1 (same color) and 21:1 (black on white). 06 Non-text contrast: the invisible button problem WCAG 1.4.11 requires interface components and meaningful graphics to carry at least 3:1 contrast against their surroundings — a measurement entirely separate from text contrast. 07 Keyboard navigation Keyboard navigation means a site can be used end to end with only the keyboard, no mouse — one of the most fundamental level A requirements of WCAG. 08 The focus indicator The focus indicator is the visual mark that lets a keyboard user see which element is currently selected. 09 Touch target size WCAG 2.2 requires touch targets to be at least 24×24 CSS pixels at level AA and at least 44×44 CSS pixels at level AAA. 10 Form error messages For a form error to count as accessible it must do three things: identify the error in text, be programmatically tied to the faulty field, and be announced to the screen reader. 11 Landmark structure and the skip link Landmark structure means marking a page’s sections — header, navigation, main content, footer — explicitly in the HTML, and it directly shapes how a screen reader user moves through the page. 12 Writing alternative text Alternative text is the text that conveys an image’s information to a user who cannot see it — and writing it well is an editorial decision, not a technical one. 13 Heading hierarchy Heading hierarchy is the ordering of a page’s h1–h6 elements so they correctly reflect the document structure — it is the screen reader user’s table of contents. 14 The reduced motion preference The operating system’s “reduce motion” setting is a signal that animations disturb the user, and a website can read that signal and change its behavior. 15 Testing with a screen reader Screen reader testing means auditing a page by listening to it through assistive technology — the one method no automated tool can replace. 16 The limits of automated auditing Automated accessibility tools can test only a portion of the WCAG criteria; the rest requires human judgment and never appears in the report. 17 Accessibility and SEO Accessibility and search engine optimization have different goals but feed largely on the same technical items — because both are written for a reader that cannot see the page.

Answer engines.

19 PAGES · PILLAR: ANSWER ENGINE OPTIMIZATION

18 Answer engine optimizationCLUSTER PILLAR Answer engine optimization is the work of increasing the probability that a site is chosen as a source in the answers produced by ChatGPT, Perplexity, Google AI Overviews and similar generative systems. 19 What is AI Overviews AI Overviews is the AI summary Google shows above its search results page, synthesized from multiple sources. 20 Getting cited in AI Overviews Getting cited in AI Overviews means a section of your page is mentioned as a source inside the summary, and this follows a selection logic different from classic ranking. 21 Being visible in ChatGPT search ChatGPT’s search mode pulls sources from the web in real time while composing an answer, and mentions the pages it used inside the answer. 22 How Perplexity picks its sources Perplexity numbers the sources it uses in every answer, and that transparency allows direct observation of which kinds of content get selected. 23 AI crawlers and robots.txt robots.txt is the plain-text file that declares which crawler may enter which parts of a site, and the same rules apply to AI crawlers. 24 llms.txt and robots.txt: two files, two jobs robots.txt tells a crawler where it may go; llms.txt tells a model what a site is and where to find what matters. 25 Entity architecture: being recognized as an entity Entity architecture is how a site establishes who it is, what it knows and what it relates to, in a form machines can recognize as an entity. 26 sameAs and digital identity sameAs is the schema field that declares an entity’s official profiles on other platforms, letting machines merge the same entity across different places. 27 JSON-LD fundamentals JSON-LD is the structured data format that declares a page’s meaning in a machine-readable form without changing a single pixel of the page. 28 FAQPage and HowTo schema FAQPage translates a page’s question-and-answer pairs into machine language; HowTo does the same for the step-by-step order of a task. 29 How to write a citable passage A citable passage is a section of text that stays correct and comprehensible on its own even when torn out of its page. 30 How to prove E-E-A-T E-E-A-T stands for experience, expertise, authoritativeness and trust — a content quality framework defined in Google’s quality rater guidelines. 31 AEO vs GEO vs SEO SEO aims at a page ranking, AEO at a question being answered directly, and GEO at being mentioned as a source inside a generated answer. 32 How to read AI crawler logs Server logs are the only direct evidence of whether AI crawlers actually visit your site and which pages they fetch. 33 Measuring brand mentions A brand mention is a brand’s name being cited without a link, and in the answer engine era it became a visibility signal independent of links. 34 Google AI Mode AI Mode is the mode in which Google search runs as a fully generative answer interface and the user can ask follow-up questions. 35 IndexNow and Bing Copilot IndexNow is an open protocol that instantly notifies search engines when a page changes, and it is supported by Bing and the Yandex family. 36 Structured data debugging Structured data errors show no symptom on the page; they only become visible through a validation tool or a test.

Performance.

19 PAGES · PILLAR: WEB PERFORMANCE

37 Web performanceCLUSTER PILLAR Web performance is a three-dimensional quality measure: how fast a page loads, how fast it responds, and how stable it stays while loading. 38 How to lower LCP LCP is the time at which a page’s largest content element in the viewport is painted, and Google counts under 2.5 seconds as good. 39 What INP is and how to measure it INP is the time from a user interaction until the page responds visually, and Google counts under 200 milliseconds as good. 40 How to zero out CLS CLS measures how much content shifts unexpectedly while a page loads or is used, and Google counts under 0.1 as good. 41 TTFB and the server response TTFB is the time between the browser sending a request and receiving the first byte from the server — the floor every other metric stands on. 42 The font swap and layout shift The font swap is the browser painting text first with a fallback family and replacing it when the real font arrives — and if the two families occupy different space, it produces layout shift. 43 Image formats: AVIF and WebP AVIF and WebP are modern image formats that deliver the same visual quality in markedly smaller files than JPEG and PNG. 44 Critical CSS Critical CSS is the minimum set of styles needed to paint the page’s first visible area, applicable immediately without waiting for a separate file. 45 The JavaScript budget A JavaScript budget is an upper limit set up front on how much code a page may download and execute — and it may not be exceeded. 46 Using lazy loading correctly Lazy loading means a resource is not downloaded until the user approaches it — and applied in the wrong place, it breaks performance instead of improving it. 47 Resource hints: preload and preconnect Resource hints are directives that tell the browser in advance which resources will be needed early or which servers it will connect to. 48 Field data and lab measurement Field data shows the performance real users experience; lab measurement shows performance simulated in a controlled environment. 49 Layout shift during scrolling: a blind spot Classic layout shift measurement looks at the page-load window; shifts occurring after the user starts scrolling are invisible in that window. 50 Reserving image dimensions Dimension reservation means telling the browser, before a resource loads, how much space it will occupy — closing the most common source of layout shift in one step. 51 How to set up a performance budget A performance budget is a set of numeric limits a page may not exceed — and it becomes a budget only when it lives in a test, not in a document. 52 Static site or content management system A static site generates its pages in advance and serves them as files; a content management system generates pages from a database at request time. 53 Render-blocking resources Render-blocking resources are the style and script files the browser cannot do the first paint without downloading and processing. 54 Caching and the content stamp Cache headers declare how long a resource may be stored; a content stamp makes the resource’s address change whenever the resource itself changes. 55 The mobile performance gap The same page runs markedly slower on mobile devices than on desktop, and the reason is not the network but processor power.

Multilingual.

16 PAGES · PILLAR: MULTILINGUAL SITE ARCHITECTURE

56 Multilingual site architectureCLUSTER PILLAR Multilingual site architecture is the full set of structural decisions that serve the same content’s versions in different languages correctly to both people and search engines. 57 What is hreflang hreflang is the markup that declares a page’s language and region versions to search engines and determines which user is shown which version. 58 hreflang errors The most frequent errors in hreflang setups are missing reciprocity, not declaring oneself, wrong code usage and conflict with the canonical address. 59 What is x-default x-default is a special hreflang value that declares the default page to show when no language version matches the user’s language. 60 URL structure: subfolder, subdomain, country domain On a multilingual site the language versions can be served under three different address structures, and the choice is the architectural decision hardest to reverse. 61 Language switcher design The language switcher is the interface component that lets the user see which language version of the site they are on and move to another version. 62 Translation or localization Translation carries text from one language to another; localization adapts the content to the target market’s culture, habits and search language. 63 The multilingual sitemap A multilingual sitemap is a site map in which every URL entry also declares all the language versions of that page. 64 Multilingual structured data On multilingual sites structured data is generated separately in every language version, and the content’s language is declared explicitly. 65 Turkish characters and URL slugs Turkish characters can technically be used in the address bar, but since in practice they become unreadable once encoded, simplified slugs are preferred. 66 German text expansion German text is markedly longer than the Turkish and English counterparts of the same content, and in multilingual design that is a constraint that must be measured. 67 Language-specific keyword research Keyword research is done separately for every language, because the term searched for the same service in different markets may not be the direct translation. 68 The automatic-redirect trap Forcing the user to a language version based on their location or browser language is a pattern that imprisons both the user and the search engine’s crawler. 69 Multilingual content management Multilingual content management governs how, when a page is updated, its counterparts in the other languages learn of it and are kept current. 70 Multilingual accessibility On a multilingual site every page and every language change must be declared; otherwise the screen reader voices the text in the wrong language. 71 Multilingual performance On a multilingual site the biggest performance variable is the font subsets: every language needs different characters, and needless characters are downloaded on every page.

Guides.

02 — KNOWLEDGE GRAPH

03 — RECORD

Answer engines.

Performance.

Multilingual.