If you are using Responsive Web Design, use meta name="viewport" tag to tell the browser how to adjust the content. If you use Dynamic Serving, use the Vary HTTP header to signal your changes depending on the user-agent. If you are using separate URLs, signal the relationship between two URLs by tag with rel="canonical" and rel="alternate" elements.
You should build a website to benefit your users, and any optimization should be geared toward making the user experience better. One of those users is a search engine, which helps other users discover your content. Search Engine Optimization is about helping search engines understand and present content. Your site may be smaller or larger than our example site and offer vastly different content, but the optimization topics we discuss below should apply to sites of all sizes and types. We hope our guide gives you some fresh ideas on how to improve your website, and we'd love to hear your questions, feedback, and success stories in the Google Webmaster Help Forum1.
Users will occasionally come to a page that doesn't exist on your site, either by following a broken link or typing in the wrong URL. Having a custom 404 page30 that kindly guides users back to a working page on your site can greatly improve a user's experience. Your 404 page should probably have a link back to your root page and could also provide links to popular or related content on your site. You can use Google Search Console to find the sources of URLs causing "not found" errors31.
On April 24, 2012 many started to see that Google has started to penalize companies that are buying links for the purpose of passing off the rank. The Google Update was called Penguin. Since then, there have been several different Penguin/Panda updates rolled out by Google. SEM has, however, nothing to do with link buying and focuses on organic SEO and PPC management. As of October 20, 2014 Google has released three official revisions of their Penguin Update.
Link text is the visible text inside a link. This text tells users and Google something about the page you're linking to. Links on your page may be internal—pointing to other pages on your site—or external—leading to content on other sites. In either of these cases, the better your anchor text is, the easier it is for users to navigate and for Google to understand what the page you're linking to is about.

To prevent users from linking to one version of a URL and others linking to a different version (this could split the reputation of that content between the URLs), focus on using and referring to one URL in the structure and internal linking of your pages. If you do find that people are accessing the same content through multiple URLs, setting up a 301 redirect32 from non-preferred URLs to the dominant URL is a good solution for this. You may also use canonical URL or use the rel="canonical"33 link element if you cannot redirect.

When Googlebot crawls a page, it should see the page the same way an average user does15. For optimal rendering and indexing, always allow Googlebot access to the JavaScript, CSS, and image files used by your website. If your site's robots.txt file disallows crawling of these assets, it directly harms how well our algorithms render and index your content. This can result in suboptimal rankings.
More than three billion people in the world are active on the Internet. Over the years, the Internet has continually gained more and more users, jumping from 738 million in 2000 all the way to 3.2 billion in 2015.[9] Roughly 81% of the current population in the United States has some type of social media profile that they engage with frequently.[10] Mobile phone usage is beneficial for social media marketing because of their web browsing capabilities which allow individuals immediate access to social networking sites. Mobile phones have altered the path-to-purchase process by allowing consumers to easily obtain pricing and product information in real time[11]. They have also allowed companies to constantly remind and update their followers. Many companies are now putting QR (Quick Response) codes along with products for individuals to access the company website or online services with their smart phones. Retailers use QR codes to facilitate consumer interaction with brands by linking the code to brand websites, promotions, product information, and any other mobile-enabled content. In addition, Real-time bidding use in the mobile advertising industry is high and rising due to its value for on-the-go web browsing. In 2012, Nexage, a provider of real time bidding in mobile advertising reported a 37% increase in revenue each month. Adfonic, another mobile advertisement publishing platform, reported an increase of 22 billion ad requests that same year.[12]
In addition to giving you insight into the search volume and competition level of keywords, most keyword research tools will also give you detailed information about the average or current estimated CPC for particular keywords are. This is particularly important for businesses with smaller ad budgets and this feature allows you to predict whether certain keywords will be truly beneficial to your ad campaigns or if they’ll cost too much.
In 2012 during Hurricane Sandy, Gap sent out a tweet to its followers telling them to stay safe but encouraged them to shop online and offered free shipping. The tweet was deemed insensitive, and Gap eventually took it down and apologized.[96] Numerous additional online marketing mishap examples exist. Examples include a YouTube video of a Domino's Pizza employee violating health code standards, which went viral on the Internet and later resulted in felony charges against two employees.[93][97] A Twitter hashtag posted by McDonald's in 2012 attracting attention due to numerous complaints and negative events customers experienced at the chain store; and a 2011 tweet posted by a Chrysler Group employee that no one in Detroit knows how to drive.[98] When the Link REIT opened a Facebook page to recommend old-style restaurants, the page was flooded by furious comments criticizing the REIT for having forced a lot of restaurants and stores to shut down; it had to terminate its campaign early amid further deterioration of its corporate image.[99]

Your social media content calendar lists the dates and times at which you will publish types of content on each channel. It’s the perfect place to plan all of your social media activities—from images and link sharing to blog posts and videos. It includes both your day-to-day posting and content for social media campaigns. Your calendar ensures your posts are spaced out appropriately and published at the optimal times.
In some contexts, the term SEM is used exclusively to mean pay per click advertising,[2] particularly in the commercial advertising and marketing communities which have a vested interest in this narrow definition. Such usage excludes the wider search marketing community that is engaged in other forms of SEM such as search engine optimization and search retargeting.
The world is mobile today. Most people are searching on Google using a mobile device. The desktop version of a site might be difficult to view and use on a mobile device. As a result, having a mobile ready site is critical to your online presence. In fact, starting in late 2016, Google has begun experiments to primarily use the mobile version of a site's content42 for ranking, parsing structured data, and generating snippets.
Facebook and LinkedIn are leading social media platforms where users can hyper-target their ads. Hypertargeting not only uses public profile information but also information users submit but hide from others.[17] There are several examples of firms initiating some form of online dialog with the public to foster relations with customers. According to Constantinides, Lorenzo and Gómez Borja (2008) "Business executives like Jonathan Swartz, President and CEO of Sun Microsystems, Steve Jobs CEO of Apple Computers, and McDonalds Vice President Bob Langert post regularly in their CEO blogs, encouraging customers to interact and freely express their feelings, ideas, suggestions, or remarks about their postings, the company or its products".[15] Using customer influencers (for example popular bloggers) can be a very efficient and cost-effective method to launch new products or services[18] Among the political leaders in office, Prime Minister Narendra Modi has the highest number of followers at 40 million, and President Donald Trump ranks second with 25 million followers.[19] Modi employed social media platforms to circumvent traditional media channels to reach out to the young and urban population of India which is estimated to be 200 million.

In 2007, Google announced a campaign against paid links that transfer PageRank.[30] On June 15, 2009, Google disclosed that they had taken measures to mitigate the effects of PageRank sculpting by use of the nofollow attribute on links. Matt Cutts, a well-known software engineer at Google, announced that Google Bot would no longer treat any nofollow links, in the same way, to prevent SEO service providers from using nofollow for PageRank sculpting.[31] As a result of this change the usage of nofollow led to evaporation of PageRank. In order to avoid the above, SEO engineers developed alternative techniques that replace nofollowed tags with obfuscated JavaScript and thus permit PageRank sculpting. Additionally several solutions have been suggested that include the usage of iframes, Flash and JavaScript.[32]