Semantic Markup refers to the idea that all HTML markup should convey the underlying meaning of its content, not it's appearance. Every HTML document has an outline, which dictates how search engines and browsers will read and render the page aspects in the proper order. In turn, graphical styles of the content within the outline should be managed by the cascading style sheet (CSS). Appropriate semantics should be used in lieu of undefined as the most efficient and optimized method of semantic markup.
SEO stands for SEarch Engine Optimization, which is the effort of increasing the volume and quality of internet traffic directed toward your website from search engines like Google or Yahoo. The primary goal of SEO is to develop growning and organic web visits and better placements in search engines results. There are several aspects that inpact SEO, including key words used on the website, links to the site from other sites, and mobile optimization. Overall, SEO is primarily achieved by making the site as search engine friendly as possible.
Web accessibility is about ensuring websites work for the widest possible audience. We have a responsibility to develop a web presence that works in the most inclusive way possible. Web accessibility has the potential to benefit everyone, inculding those with or without a disability impacting their web usage. Furthermore, accessibility often helps with SEO, usability, and customer satisfaction with web enabled services. There are several methods available to aid in ensuring web accessibility including, HTML validation, keyboard testing, vision and color chouce awareness, responsive development, and other methodologies.