{"id":186,"date":"2019-06-04T12:29:18","date_gmt":"2019-06-04T16:29:18","guid":{"rendered":"https:\/\/pressbooks.library.ryerson.ca\/iwacc\/?post_type=chapter&#038;p=186"},"modified":"2019-11-19T11:03:17","modified_gmt":"2019-11-19T16:03:17","slug":"introduction-to-perceivable","status":"publish","type":"chapter","link":"https:\/\/pressbooks.library.torontomu.ca\/iwacc\/chapter\/introduction-to-perceivable\/","title":{"raw":"Introduction to Perceivable","rendered":"Introduction to Perceivable"},"content":{"raw":"<div style=\"margin: 1em 0;padding: 1em;border: 1px solid #ddd;border-left: 10px solid #d35400\">\r\n<h2>Principle 1: Perceivable<\/h2>\r\nInformation and user interface components must be presentable to users in ways they can perceive.\r\n\r\n<\/div>\r\n<div style=\"margin: 1em 0;padding: 1em;border: 1px solid #ddd\" title=\"definition\">\r\n\r\n<strong>Definition<\/strong>\r\n\r\n<strong>Perceive<\/strong>: 1. To become aware of (something) through the <strong>senses<\/strong>, especially the sight; recognize or observe. 2. To come to <strong>comprehend<\/strong>; grasp (dictionary.com)\r\n\r\n<\/div>\r\n<h3>The Principle Explained<\/h3>\r\n<h4>Sensing<\/h4>\r\nAs suggested in the first definition above, people must be able to perceive web content through one or more of their senses. When a person cannot see or hear, for instance, and an alternate means of perceiving is not available, then that content becomes inaccessible to them.\r\n\r\nContent may not be perceivable if web authors:\r\n<ul>\r\n \t<li>choose small or hard-to-read fonts;<\/li>\r\n \t<li>specify colours for fonts that do not provide sufficient contrast with the background;<\/li>\r\n \t<li>leave out a text description of a photograph;<\/li>\r\n \t<li>do not provide captions or a transcription for multimedia and audio content; or<\/li>\r\n \t<li>require timed responses.<\/li>\r\n<\/ul>\r\nPerceptual barriers occur when information is communicated entirely through one of the following:\r\n<ul>\r\n \t<li>Sight<\/li>\r\n \t<li>Sound<\/li>\r\n<\/ul>\r\nMost people perceive web content through sight and sound. When content is communicated exclusively through one sense, such as sight, some people will not be able to perceive it.\r\n\r\nThese types of perceptual barriers are addressed through <strong>Guidelines<\/strong> <strong>1.1<\/strong>, <strong>1.2<\/strong>, and <strong>1.4<\/strong>.\r\n<h4>Comprehending<\/h4>\r\nThe second definition suggests people must be able to comprehend or grasp web content. The ability to comprehend web content can be affected by the structure, the relationships between elements, its complexity, or consistency in the presentation.\r\n\r\nPerceptual barriers of this nature occur when:\r\n<ul>\r\n \t<li>information is poorly structured;<\/li>\r\n \t<li>navigation or presentation is inconsistent;<\/li>\r\n \t<li>the focus ordering of content is illogical;<\/li>\r\n \t<li>functional elements are not effectively described or labelled;<\/li>\r\n \t<li>content operates only in a single display orientation; or<\/li>\r\n \t<li>instructions reference content solely through shape, colour, size, or visual location.<\/li>\r\n<\/ul>\r\nThese types of perceptual barriers are addressed by<strong> Success Criterion 1.3.3<\/strong> (sensory characteristics), described later in this unit.\r\n<div style=\"margin: 1em 0;padding: 1em;border: 1px solid #ddd;border-left: 10px solid #0000ff\">\r\n\r\n<strong>Suggested Reading: <\/strong><a href=\"https:\/\/www.w3.org\/TR\/WCAG21\/#perceivable\">WCAG 2.1 Perceivable<\/a>\r\n\r\n<\/div>","rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_80 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Contents<\/p>\n<label for=\"ez-toc-cssicon-toggle-item-69d4533d9ec31\" class=\"ez-toc-cssicon-toggle-label\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/label><input type=\"checkbox\"  id=\"ez-toc-cssicon-toggle-item-69d4533d9ec31\"  aria-label=\"Toggle\" \/><nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/pressbooks.library.torontomu.ca\/iwacc\/chapter\/introduction-to-perceivable\/#Principle_1_Perceivable\" >Principle 1: Perceivable<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/pressbooks.library.torontomu.ca\/iwacc\/chapter\/introduction-to-perceivable\/#The_Principle_Explained\" >The Principle Explained<\/a><ul class='ez-toc-list-level-4' ><li class='ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/pressbooks.library.torontomu.ca\/iwacc\/chapter\/introduction-to-perceivable\/#Sensing\" >Sensing<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/pressbooks.library.torontomu.ca\/iwacc\/chapter\/introduction-to-perceivable\/#Comprehending\" >Comprehending<\/a><\/li><\/ul><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n<div style=\"margin: 1em 0;padding: 1em;border: 1px solid #ddd;border-left: 10px solid #d35400\">\n<h2><span class=\"ez-toc-section\" id=\"Principle_1_Perceivable\"><\/span>Principle 1: Perceivable<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Information and user interface components must be presentable to users in ways they can perceive.<\/p>\n<\/div>\n<div style=\"margin: 1em 0;padding: 1em;border: 1px solid #ddd\" title=\"definition\">\n<p><strong>Definition<\/strong><\/p>\n<p><strong>Perceive<\/strong>: 1. To become aware of (something) through the <strong>senses<\/strong>, especially the sight; recognize or observe. 2. To come to <strong>comprehend<\/strong>; grasp (dictionary.com)<\/p>\n<\/div>\n<h3><span class=\"ez-toc-section\" id=\"The_Principle_Explained\"><\/span>The Principle Explained<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<h4><span class=\"ez-toc-section\" id=\"Sensing\"><\/span>Sensing<span class=\"ez-toc-section-end\"><\/span><\/h4>\n<p>As suggested in the first definition above, people must be able to perceive web content through one or more of their senses. When a person cannot see or hear, for instance, and an alternate means of perceiving is not available, then that content becomes inaccessible to them.<\/p>\n<p>Content may not be perceivable if web authors:<\/p>\n<ul>\n<li>choose small or hard-to-read fonts;<\/li>\n<li>specify colours for fonts that do not provide sufficient contrast with the background;<\/li>\n<li>leave out a text description of a photograph;<\/li>\n<li>do not provide captions or a transcription for multimedia and audio content; or<\/li>\n<li>require timed responses.<\/li>\n<\/ul>\n<p>Perceptual barriers occur when information is communicated entirely through one of the following:<\/p>\n<ul>\n<li>Sight<\/li>\n<li>Sound<\/li>\n<\/ul>\n<p>Most people perceive web content through sight and sound. When content is communicated exclusively through one sense, such as sight, some people will not be able to perceive it.<\/p>\n<p>These types of perceptual barriers are addressed through <strong>Guidelines<\/strong> <strong>1.1<\/strong>, <strong>1.2<\/strong>, and <strong>1.4<\/strong>.<\/p>\n<h4><span class=\"ez-toc-section\" id=\"Comprehending\"><\/span>Comprehending<span class=\"ez-toc-section-end\"><\/span><\/h4>\n<p>The second definition suggests people must be able to comprehend or grasp web content. The ability to comprehend web content can be affected by the structure, the relationships between elements, its complexity, or consistency in the presentation.<\/p>\n<p>Perceptual barriers of this nature occur when:<\/p>\n<ul>\n<li>information is poorly structured;<\/li>\n<li>navigation or presentation is inconsistent;<\/li>\n<li>the focus ordering of content is illogical;<\/li>\n<li>functional elements are not effectively described or labelled;<\/li>\n<li>content operates only in a single display orientation; or<\/li>\n<li>instructions reference content solely through shape, colour, size, or visual location.<\/li>\n<\/ul>\n<p>These types of perceptual barriers are addressed by<strong> Success Criterion 1.3.3<\/strong> (sensory characteristics), described later in this unit.<\/p>\n<div style=\"margin: 1em 0;padding: 1em;border: 1px solid #ddd;border-left: 10px solid #0000ff\">\n<p><strong>Suggested Reading: <\/strong><a href=\"https:\/\/www.w3.org\/TR\/WCAG21\/#perceivable\">WCAG 2.1 Perceivable<\/a><\/p>\n<\/div>\n","protected":false},"author":100,"menu_order":1,"template":"","meta":{"pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"class_list":["post-186","chapter","type-chapter","status-publish","hentry"],"part":26,"_links":{"self":[{"href":"https:\/\/pressbooks.library.torontomu.ca\/iwacc\/wp-json\/pressbooks\/v2\/chapters\/186","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pressbooks.library.torontomu.ca\/iwacc\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/pressbooks.library.torontomu.ca\/iwacc\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/pressbooks.library.torontomu.ca\/iwacc\/wp-json\/wp\/v2\/users\/100"}],"version-history":[{"count":11,"href":"https:\/\/pressbooks.library.torontomu.ca\/iwacc\/wp-json\/pressbooks\/v2\/chapters\/186\/revisions"}],"predecessor-version":[{"id":1310,"href":"https:\/\/pressbooks.library.torontomu.ca\/iwacc\/wp-json\/pressbooks\/v2\/chapters\/186\/revisions\/1310"}],"part":[{"href":"https:\/\/pressbooks.library.torontomu.ca\/iwacc\/wp-json\/pressbooks\/v2\/parts\/26"}],"metadata":[{"href":"https:\/\/pressbooks.library.torontomu.ca\/iwacc\/wp-json\/pressbooks\/v2\/chapters\/186\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/pressbooks.library.torontomu.ca\/iwacc\/wp-json\/wp\/v2\/media?parent=186"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/pressbooks.library.torontomu.ca\/iwacc\/wp-json\/pressbooks\/v2\/chapter-type?post=186"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/pressbooks.library.torontomu.ca\/iwacc\/wp-json\/wp\/v2\/contributor?post=186"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/pressbooks.library.torontomu.ca\/iwacc\/wp-json\/wp\/v2\/license?post=186"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}