Accessibility is the main consideration for every good web designer. It is important to make your website available to the widest possible audience; there are several ways you can do this:
Cross-browser compatibility – This involves checking and testing sites in different browsers, eg IE7, IE8, Mozilla Firefox, Google Chrome. This is very basic accessibility and is still a stumbling block for many sites.
Using alt tags – Alt tags must be used on any image on a website that has a purpose other than being decorative, if the image is clear enough, a simple description is sufficient, if more complicated, the chart must be explained in the page content or use the "longdesc" tag.
Alt tags make things easier for individuals who are partially visible and use a screen reader program. It takes a little effort to make the website accessible in this way and will help you reach a wider audience. You can know about website compliance with accessibility standards from various online sources.
Text resizing – Changing the size of pages and text is usually done in the browser (using ctrl + (-)) but they all have differences in how they make pages so it is good to check how many pages are in each browser to make sure it's working properly.
Skip link – Skip link is also useful for screen readers, the anchor link added above the navigation allows people who use screen readers to go through the website navigation section and directly to the content to save it having to listen to each level of navigation every time they arrive on the page.
Contrast – Including high contrast alternative style sheets can be useful for elderly users and people with visual impairments who do not use screen readers. High contrast can make the text easier to read for some parties and allow them to get the best experience from the website. Having low contrast color choices can also be beneficial for dyslexics, who may suffer from sensitivity to high contrast colors.