SEO (Search Engine Optimization) is the practice of optimizing any website content to be discovered through a search engine’s organic search results ranking pages. It's a free-of-cost way to optimize your website and get organic search traffic to your website for free. Common tasks associated with SEO include creating high-quality content, optimizing content around specific keywords, and building quality backlinks. Search Engine Optimization is an important key if you want to get more organic traffic to your website.
SEO conceptually comes under 2 types:
Black HAT SEO: Black hat SEO can be referred to as a set of procedures that are used to increase a website or page's rank in search engines through means that violate the search engine's terms of service.
White HAT SEO: White HAT SEO can refer to any practices that improve search engine results page (SERP) rankings while maintaining the integrity of your website and staying within the search engine's terms of service.
SEO can be done in 2 ways:
On-page SEO: It is the practice of optimizing individual web pages to rank higher and increase more relevant traffic in search engines. On-page refers to both the content and HTML source code of a page that has to be optimized, as opposed to off-page SEO which refers to links and other external signals.
Off-page SEO: It refers to all of the activities that you and others do away from your website to raise the ranking of a page with search engines. Many people can associate off-page SEO with link building, but it goes beyond that.
Mostly, the SEO experts take responsibility for the website's SEO. Today many digital marketing agencies hire SEO experts to maintain their SEO plans.