Here are few reasons why a website needs search engine optimization

1. Goal of SEO optimization is to improve website’s rankings in search results. And the purpose of achieving high rankings is to attract more traffic for getting the quality leads.

2. It's a long term,a very small amount investment to keep your website on top rankings. Results start coming with in some time having great conversion rates for specific keywords. Same can be verified with the Analytics data.

3. SEO is Pull Marketing based on customer intent. It brings your business in front of the actively searching target audience. It plays an important role to offer information about products and services.

4. SEO helps to build credibility and authority like if you have done SEO and Content marketing for your website, user will 

5. Search engine can customize search results based on user's recent search behavior, location, web history, demographic etc. It means a lot of searches will come on SERP as according to the pre feed customized data of target audience.

6. Every other business is in race to get better results for the website. SEO helps to stay ahead of competitors.

7. Google’s ultimate goal is to provide the best possible results for their users. As a result, many of their algorithm updates focus on making sure that they’re directing users to sites that not only provide relevant content, but also a great user experience.
  

In SEO, search engines (For example: Google, Bing, Yahoo,Baidu etc.) analyze the content of a web page to determine if it would be relevant for any given search query. 

Search Engines have primarily three functions:

1. Crawling: It's a process in which team of robots find new and updated content. Here content means a web page, a video, an image, a PDF etc.

Google bot starts out by fetching a few web pages, and then follows the links on those web pages to find new URLs. Hence a massive database of URL's is collected called Caffeine.Crawling is the first part of having a search engine recognize your page and show it in search results.

2. Indexing: It's a process in which the search engine stores and organize the data collected in Index (After crawling). The indexing of your content by Google is determined by system algorithms that take into account user demand and quality checks. 

3. Ranking: To show the results in such a relevant order in SERP for any user's query is called Ranking. In general, you can assume that the higher a website is ranked, the more relevant the search engine believes that site is to the query.

It’s possible to block search engine crawlers from part or all of your site, or instruct search engines to avoid storing certain pages in their index. While there can be reasons for doing this, if you want your content found by searchers, you have to first make sure it’s accessible to crawlers and is indexable

Google’s Audience solutions is a set of strategies and products that help you reach high-value customers in the moments when they’re ready to buy the products you offer. 
It allows to condition bids, creatives, and keywords based on various customer groups. BAsed on different marketing goals Audience groups are created.

If the goal is to create Awareness then we can choose from Detailed Demographics and Affinity Audience.

Detailed Demographics allows advertisers to reach people based on advanced demographic criteria like marital status, education, parenting stage, and homeownership.

Affinity Audiences aggregates people who have demonstrated a strong interest in a given topic.

If the goal is to drive consideration we can choose In- Market Audience, RLSA, Similar Audience.

In-Market Audiences is a powerful way to drive consideration among people who are actively researching the products or services you offer and who we've inferred are in-market to buy them.

RLSA (Remarketing List for Search Ads) helps you reach people who have engaged with your website or YouTube channel in the past.

Similar Audiences for Search helps you find new customers that share the behaviors and characteristics of your remarketing audience segments. 

If Marketing goal is to Increase purchases and loyalty with your existing customers then we can choose from Customer Match and RLSA

Customer Match allows you to upload your own data into Google Ads and reach custom segments across devices. Find your loyal customers, exclude your current customers, and expand to reach those that resemble your customers.

Remarketing Lists for Search Ads can help you reach those who were your customers in the past 
 

Location Extensions: Give directions to the business: Location extensions let you show your business address, phone number, and a map marker alongside your ad text. On mobile devices, there’s a link with directions to your business.

Location extensions are served via the Google My Business (GMB) account. Make sure information such as address and phone number are updated.

Affiliate location Extensions: Affiliate location extensions allow product manufacturers to drive visits to retail partners that sell their products. The format displays the headline and URL for the manufacturer’s website, ad text for the manufacturer’s product, and the nearest retailer.
In the Google Ads interface, select retail chains or automotive dealerships to highlight all of the nearby locations where consumers can find your products.

Call Extensions:If you’re looking to get calls from customers, use call extensions. These extend ads with a phone number, allowing mobile users to directly call your business.

Enable phone call conversions reporting in account settings to assess which campaigns, ad groups, and keywords are most effective at driving call conversions.

App Extensions:App extensions are great if you have an app to promote. This format gives you the option of driving traffic to your website or the app store from a single text ad. 

By giving the option to install the app via the extension, you increase your app’s visibility and grow your installation base.

Price Extensions: Price extensions let you showcase your services and range of products alongside their respective prices. They’re available globally in several languages and currencies.

Don't use promotional copy in descriptive lines also don't repeat headlines and description lines.

Promotion Extensions: Promotion extensions allow you to quickly and prominently display information about your promotions without having to update every single ad.Promotion extensions show below your ads in an eye-catching format.

Choose to show your promotion extensions within the date of the occasion, or specify the dates, days of the week, or times of day you want them to show.

Message Extensions: Message extensions are a mobile-only format that enables clients to easily connect with a growing segment of users who prefer to text.

There are three extensions every marketer should be using to enhance their text ad: 1) Sitelinks 2)Callout extensions and 3) Structured snippets.

1) Sitelinks: It directs to specific sections of the website. Sitelinks are additional links that appear just under the text of your search ads, directing users to specific pages of your website.
Sitelinks are easy to manage as system automatically displays the best performing or most relevant sitelinks for each query. It helps to increase CTR and eventually the conversions.

It is recommended to implement 8-10 active sitelinks/ campaign. It should be clearly mentioned on sitelink title what users will find on the landing page.

2) Callout extensions: Callout extensions are short, specific (25-character) snippets of text. They can be used to highlight information about value-adding attributes of the business, products, or services. 

Keep your callouts as short and specific as possible, and include at least six of them in your campaigns.Consider callouts that are unique offerings.

3) Structured Snippets: Structured snippets allow you to describe features of a specific product or range of products or services offered by the business before users click on the ad.

When you give users specific information about what you're offering before they visit your website, they'll be more likely to convert after clicking.

Search ad extensions can drive direct action when users interact with your ads.    It improves user experiences and increases engagement.
Ads are a part of the Google ecosystem and they have to be relevant to provide a good user experience and encourage users to take action. That’s why in order to respond to user behavior and demand ad extensions  provide the right users with the right information at the right moment.

Ad extensions enrich text ad by showing extra information about the advertiser's business. Google Ads automatically serves the ad extensions that are predicted to have a positive impact on performance. At any given time, up to four extensions can show for a particular query or device. 

Text Ads are the ads made up of Text. It helps to get your business in front of people when they’re searching for products or services like yours on the Google Search Network. Text ads should be informative, relevant, and engaging. 

To create a text ad, you need a headline, URL, and description.

Headline:  Up to three headline fields are available with up to 30 characters each. The first two headline fields are required, and the third is optional.Include at least one of your keywords in your headline

Description: Two description fields — with up to 90 characters each — let you highlight unique details about your product or service. On mobile, where space is tight, Google Ads optimizes your ad to show the highest-performing text.
Highlight what makes your business unique: Include prices, promotions, and exclusive offers etc. Empower customers to take action, it can be done by using strong and unique CTA's like purchase, call today, order, browse, sign up, or get a quote.

URL: The URL shows your website address. It gives people an idea of where they'll go when they click your ad.Match your ad to your landing page. Two optional path fields can be added to your display URL.  Each field can hold up to 15 characters. This feature gives users an idea of the content they’ll see upon clicking your ad.

Google Ads uses an auction system to rank the ads that appear on the search results page, and to determine the cost for each ad click. The order in which ads appear on the page is based on a calculation we call Ad Rank. 

Google Ads calculates Ad Rank for every ad in the auction. Ad Rank determines your ad position and whether your ads are eligible to show at all. Generally speaking, the ad with the highest Ad Rank gets to show in the top position, and the ad with the second highest Ad Rank gets to show in the second position.

Ad Rank depend upon the five factors.
1. Bid: Bid is the amount you're telling Google Ads the maximum amount you're willing to pay for a click on your ad. 

2. Auction Time Ad Quality: It includes click through rate, ad relevance, and landing page experience. Quality Score is an aggregated estimate of our assessment of the quality of your ad.(Quality Score is the rating whcih Google use to determine the relevance of keywords and Google Ads. Formula for Quality Score = 1 + Landing Page Experience weight + Ad Relevance weight + CTR weight)

3. Ad Rank Threshold: To help ensure high-quality ads, we set minimum quality thresholds that an ad must achieve to show in a particular ad position.

4. Context of query: With the ad auction, context matters. When calculating Ad Rank, we look at the search terms the person has entered, the person’s location at the time of the search, the type of device they’re using, the time of the search, the nature of the search terms, other ads and search results that show on the page.

5. Ad Extensions and Formats impact: Google Ads estimates how extensions and other ad formats you use will impact your ad's performance.

Matching Keyword to what your customers may use when looking for your products or services is called keyword targeting which is a very important building block for marketing Campaigns.

There are five match type options for your keywords.

1. Broad Match
2. Broad Match Modifier
3. Phrase Match
4. Exact Match
5. Negative

1. Broad Match
Broad match shows ads if a keyword or any variations like misspellings, synonyms or related searches are included in a user’s search terms.

2. Broad Match Modifier
Adding a + sign in front of a keyword turns it into a broad match modifier. This prompts your ads to appear only if the keyword or its close variations are in any part of the search terms.

3. Phrase Match
Placing quotation marks around the keywords turns them into phrase match. This prompts your ads to appear only if the keywords within the quotation marks or close variations of them match a user’s search term.

4. Exact Match
To use exact match, place brackets around the keywords. This way, your ads will only show if the search means the same thing as your keyword. It may include close variations of your keyword, like misspellings, plurals, and synonyms.

5. Negative
Adding a minus sign in front of the keyword scooter makes it a negative keyword (-scooter). This means ads won’t show if someone includes that negative keyword in their search.

Below is explained with an example for each match Type Keyword: