Hi, I'm Kartik and this session is on Search Engine Optimization or SEO. Now, when you enter a search query on a search engine like Google, your search results consist of organic results and sponsored results. Organic results are essentially those webpages that are most relevant to your search query as determined by the search engine algorithm. Sponsored results on the other hand are results based on payments made by advertisers to the search engine. Search engine optimization or SEO, focuses on placement among the organic results. And search engine marketing focuses on placement among the sponsored results. In this session we're going to talk a little more about search engine optimization, and in the later session, we'll discuss search engine marketing. To understand search engine optimization, it is first useful to understand how search engines work. Search engines perform three main functions. The first function is to gather all the pages on the web. This is also known as crawling or sometimes called spidering. The second function is to organize the content of the pages that have been downloaded to allow for easy look up later. This is called indexing. And the process of indexing is similar to the process of generating an index for a book. The index essentially lists all the pages in that book that contain that term. And similarly the index in a search engine might refer to all the web pages that somehow relate to the term of interest. And finally, in response to a search query the search engine determines which pages are relevant to the search query and ranks them in order of relevance. Accordingly, based on these three steps of crawling, indexing, and ranking. I'm now going to discuss three important strategies for search engine optimization. The first strategy is to ensure all your web pages are in fact crawled by search engines. To do so, it's useful to maintain a sitemap. A sitemap is essentially a list of all pages on your website. With the link structure that clarifies how a user might navigate from one page to another. For example, the image to our right has the sitemap for one sample website. A sitemap makes it easy for a search engine to discover all your web pages. Dynamic content should also be added to sitemaps so that you can ensure that dynamic pages are also discovered by search engines, and those pages show up in search engine results. If you're finding that a page that is generated dynamically isn't getting indexed, then you might want to create static versions of that webpage. The second strategy is based on indexing. Recollect that the index records the pages, that are relevant for any given keyword. Keywords are essentially words or phrases that represent the content of a webpage. The second strategy is based on indexing. Recollect that an index records the pages that are relevant for any given keyword. Keywords are essentially words or phrases that represent the content of your website. So in order to make sure that your website is indexed for the right set of keywords, you want to use these keywords on your website prominently. You might determine which keywords to use on your website based on search volume for different key words, and based on the level of competition you face for these keywords. For example, consider that you are an online florist that sells flowers at a lower price than many competitors. Based on that you might determine there are several keywords that are relevant for you. You might discuss on your website you're a florist. You might instead choose to focus on being a wedding florist, you might alternatively discuss that you're a florist that specializes in Valentine's Day flower delivery, or you might discuss the fact that you are cheap, or lower-cost florist, and so on. And in trying to determine what's the right set of keywords to focus on, we might look at monthly search volumes. And one might determine that there are certain terms, like florist, that are searched a lot more than some others, like cheap florist. On the other hand, search terms like florists are also highly competitive, and there's just too many other companies that end up being relevant for the search query. In contrast, notice for wedding florist you have reasonable search volume, but it is not as competitive as florist is. And you might determine these are the kinds of keywords you might focus on where you have high search volume, but not as high competition. Now figuring all this out is not as hard as it might seem. There are several free tools, that are available to advertisers, that can be used to get this kind of information. For example one tool that I commonly use is Google's Adword keyword planner. The next strategy is ranking. Ranking on search engines depends on the appearance of keywords or search terms on your website and on the number of inlinks that your Website gets. We've already discussed keyword selection and placement on your website. Now, inlinks are another important considerations. Inlinks essentially refer to links to your website from other websites. The number and quality of inlinks into a web page indicates how authoritative the page is. And generally, the more authoritative a page, the higher that page is going to be ranked. So you want to ensure you get a lot of links, and a lot of high quality links, into your website. It's worth noting here that black hat techniques, like getting lots of links from fake blogs, are usually not very effective, because search engines prioritize links from high quality pages. For example consider the image to our right. In this image each circle denotes a webpage and arrows connecting to circles indicate a link going from one page to the other. In this example page b has a lot of in links coming into this website. And therefore it has high score of 38.4%, which indicates that it's going to be ranked high in search engine results when there is a relevant search query. In contrast, the purple pages have almost no inlinks and therefore they have a much lower score. Now notice again over here that page C only has one inlink. And despite that, it has a high score of 34.3%. And page E has a lot of inlinks and despite that has a lower score of 8.1%. And this is because page E gets a lot of links from poor quality websites whereas page C gets a link from an authoritative website. And therefore, the idea is to get a lot of links from other websites and focus on links from prominent websites. So this is where PR helps. When you have links from media outlets, that increases the likelihood that your website will also rank high in search engine results. Finally, let's talk about the role of blogs. The primary purpose of blogs is to provide timely information to your customers or to establish thought leadership or to engage in some sort of dialogue with your users. However, blogs can also be useful with search engine optimization. By writing more blog posts you create more content. And by offering more content you increase the chances that your website will be indexed for more search queries. And this will ultimately help bring in more traffic. In conclusion search engines can be a great source of free traffic for your website by focusing on website content creation. And on generating inlinks from other website, you can help ensure that your website shows up high on search engine results and gets as much free traffic as possible.