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Digital Marketing - Study Notes:

3i principles

The 3i principles are the foundation tenets of the Digital Marketing Institute framework for successful search marketing. They stand for Initiate, Iterate, Integrate. By keeping these 3is in mind as you progress through this course, when the time comes to develop your own search marketing strategy, you will find it much easier, more accurate, and well-informed. The core value of the DMI 3i methodology is the centrality of the consumer, who we optimize towards and seek out wherever they are. Let’s take a look at what exactly each of these 3is mean.

  • Initiate: Rather than starting with yourself, start with the customer - with what they are actually doing - and work backwards towards your search strategy.
  • Iterate: This involves continually learning from your online search engagement with your customers and acting on that.
  • Integrate: This involves integrating all of the search channels coherently.

What is a search engine?

A search engine is a program that searches for and identifies items in a database that correspond to keywords or characters specified by the user, used especially for finding particular sites on the web. Search engines are an applied form of information retrieval, which is a field of study in computer science.

Search engine results page (SERP)

A search engine results page (SERP) is displayed by a search engine in response to a query from a searcher. Search engines have one major function: they provide answers to user queries through lists of relevant pages that they have retrieved and ranked for relevancy.

Paid advertising

Paid advertising makes up the bulk of a search engine results page above the fold, because this is where search engines like Google make most of their revenue. When people click on ads, Google gets paid, and that’s the bulk of their profits. These paid ads are the result of Google Ads advertising.

Organic results

Organic search results are shown on a SERP below the paid ads. Google feels these are the most relevant and trustworthy results to show for any given query. The order in which they appear represents the relevance and trust Google accords to these results. A high ranking on Google means that a webpage is shown near the top of the organic search results.

Users tend to click more on the organic search results than on the paid ads, as the former are considered more trustworthy and relevant. Usually when users recognize an ad as a paid ad, they’re less likely to click on it, and prefer to click on the organic results below it.

Search engine processes - organic

Generally speaking, all search engines have three main processes: the crawler, the indexer, and the query engine.

  • Crawler: The crawler, which in Google is known as Googlebot, is a piece of software that continuously crawls the web trying to find new links and updated pages.
  • Indexer: When the crawler finds something new, it sends them on to the indexer, which tries to make sense of what the crawler has found, and sees what kind of keywords that page could be ranked for. The indexer then builds an index of rankable webpages.
  • Query engine: The query engine is the front end of Google, where the user enters search terms, and where Google interprets what the user has typed in, and selects the best possible results from the index to show in its search result. Again, relevancy and trust are the key factors that Google uses to determine which of the new results deserves to be ranked near the top.

Search engine processes – paid advertising

The process for paid advertising is very different from the one for organic search. Advertisers choose keywords that they want to advertise on. Whenever their keyword is searched for, it triggers a live auction.

Google determines which ad is shown first and second and third, depending on the bids that the advertiser has put in for that particular keyword, as well as the quality score of their ad and their landing page. Those combined result in an ad rank, and the ad with the highest ad rank is shown as the first ad.

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Barry Adams

Barry Adams is the founder of Polemic Digital, which won Best Small SEO Agency at the 2016 UK Search Awards. He has been an active practitioner since 1998 and is co-chief editor for State of Digital. His clients include national brands like EMO Oil and The Sun, multinationals and local businesses.

Data protection regulations affect almost all aspects of digital marketing. Therefore, DMI has produced a short course on GDPR for all of our students. If you wish to learn more about GDPR, you can do so here:

DMI Short Course: GDPR

You will not be assessed on this content in your final exam.


Barry Adams
Skills Expert

This module introduces the core principles and concepts of search marketing. It demonstrates how the use of organic search can benefit marketing campaigns. It introduces the key concepts of paid search and the ways in which it can be used to improve the performance of a campaign. It also outlines how to measure the success of a search campaign and how it fits within a wider digital marketing strategy.