![]() When doing so, layout tables typically define pixel values to attempt to control exact positions. When author's use tables for layout, they are typically doing so to get more precise and (supposedly) flexible control over the positioning of elements within the page. can help you visually see the linearized reading order of tables. Tools, such as WAVE, the Web Developer Toolbar, etc. If you view the source code for this table, you'll notice that the source code order matches the order specified above. Here is the same table with borders visible and numbers added to each cell to indicate the order in which the screen reader will read them: 1 - Basement Why does this difference exist between the visual order and the screen reader order? To answer this question, we have to look at the table structure. The screen reader will hear (or feel via Braille): "Basement UP! Toilets Flush Must" The visual user will read: "Basement Toilets Must Flush UP!" Here is a layout table which was created for visual effect: Basement ![]() Let's take a look at an example in which reading order becomes an issue. are NEVER used within layout tables, otherwise the screen reader may incorrectly present the table as a data table causing increased overhead and confusion. Because of this, it's vital that data table markup, such as, , etc. So how does a screen reader know if a table is a data table or a layout table? They perform some analysis of the table markup and structure to 'guess'. For data tables, however, they will identify the presence of the table including number of columns and row, provide table navigation functionality, read row and column headers, etc. For layout tables, they simple read the content of table based on the source code order. Screen readers treat layout tables and data tables very differently. People with all kinds of disabilities can easily access layout tables, as long as the tables are designed with accessibility in mind - ensuring proper linearized reading order, content scaling, etc. There are certainly many worse things that you could do in terms of accessibility. In reality, layout tables do not pose inherent accessibility issues. It is sometimes suggested, even by some accessibility advocates, that layout tables are bad for accessibility. Layout tables are also not supposed to be used in HTML5. Using CSS results in cleaner and more simple HTML code, better end user adaptability, and few potential accessibility issues. With CSS, however, there is much more flexibility in controlling page layout, so it is best to not use tables to do this. Layout tables were traditionally used to overcome limitations in visual presentation and layout using HTML. Layout tables do not have logical headers that can be mapped to information within the table cells. Tables are also commonly used for page layout. For example, here is a simple data table: Shelly's Daughters Name A table is a data table when row headers, column headers, or both are present. The original intended use of HTML tables was for tabular data. There are two basic uses for tables on the web: data tables and layout tables. Even when you do go into table reading mode, it can still be confusing if the table is not marked up properly. When you listen to tables straight through, without going into table reading mode in a screen reader, this type of information can be quite confusing. You go to a web page that has this information, and this is what you hear: ![]() You're going to a web site to find out where the biology 205 class is going to be held. ![]() If you're not a screen reader user, let's pretend that you are for just a moment. ![]()
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