The owner of a website or blog will get an income in the form of sharing profits from Google for each ad clicked by a site visitor, known as the pay per click (PPC) or pay per click system.
In addition to providing advertisements with a pay per click systems, Google AdSense also provides AdSense for search (AdSense for Search) and referral advertisements (Referrals).
In AdSense for search, website owners can install Google search boxes on their web pages. Site owners will get revenue from Google for every search that visitors make through the search box, which continues with clicks on the ads included in the search results. In referral advertisements, the site owner will receive income after clicking on the ad continuing with certain actions by the user agreed between Google and the advertiser.
Terms in AdSense
Publisher
A publisher is a person or site owner who has joined and posted AdSense ads on their site.
Ad Units
What is meant by Ad Units is the AdSense ad itself. Ad Units consist of several types and sizes. The most common is the type of text ad. When a visitor clicks on this ad unit, then (if valid) the advertiser will get the income according to the value of the CPC.
Units link
Link Units are almost the same as Ad Units, it's just that the format is similar to the menu format we usually encounter on websites. What distinguishes Link Units with Ad Units is when visitors click on this ad, it will be directed to search results pages on Google search engines. The new publisher will get income if the visitor clicks on one of the Ad Units on the page. In practice, Link Units is proven to generate more revenue than regular Ad Units.
AdSense for Content
AdSense for Content is an AdSense ad that is installed on a page. The advertisements that appear are advertisements related to the contents of the page. Or the term uses contextual concepts. Ad Units and Link Units are included in this AdSense for Content.
Alternate Ads
In AdSense for Content, ads do not always appear. The reason is, among others, because the advertising stock that is related to the content of the site has run out or Google cannot predict what the site actually contains. If this happens, by default, what is displayed is a public service ad or often known as PSA (Public Service Ads). Because of the type of donation, if clicked, this ad will not produce anything for the publisher. To overcome this, Google allows us to install Alternate Ads or alternative ads. If the Ad Units that are made have been arranged by using Alternate Ads, then if the Ad Units cannot appear, the alternative ads that have been set are displayed.
Channels
Channels are a kind of label that can be given to Ad Units, Link Units, AdSense for Search, and Referrals. One ad unit can have more than one label, and vice versa, one label can be used for more than one ad unit. On the Google AdSense report page, the results of the report will be grouped based on Channels, so the use of Channels will greatly facilitate publishers to analyze their AdSense performance. Generally, publishers will give the same Channels name to ad units on one site. If you want more detail, it's fine to give different Channels names to each ad unit on each site. Keep in mind, the maximum number of Channels allowed is 200 channels.
Page Impressions
Page Impressions are the number that shows how many times pages containing Ad Units are opened by visitors. Its value is not affected by the quantity of Ad Units in the page concerned.
Clicks
Clicks are the number of clicks on the publisher's Ad Units. In the AdSense report page, the publisher can see the total clicks he gets or based on the Ad Units or Channel.
CTR (Click through Rate)
CTR is a comparison in percent of the number of clicks received by an Ad Units with the number of views of the Ad Units. For example, one Ad Units that is displayed 40 times and clicked 10 times has a CTR value of 25% (10:40).
CPC (Cost Per Click)
CPC is the amount of money that will be obtained by the publisher if certain Ad Units are clicked. The CPC value of each Ad Units is different and is determined by many factors, including the performance and quality of the publisher's site. But in general, the maximum possible value is 20% of the value of the dynamic offer offered by the advertiser.
eCPM (Effective CPM)
eCPM or CPM (Cost Per Million) is the result of the division between the amount of publisher revenue and the number of page impressions (per 1,000) he gets from his advertisements. For example, a publisher that generates USD 200 of 50,000 impressions will have a CPM value of USD 4 (USD 200 divided by 50).
AdSense program policies
Although the AdSense program provides great benefits, Google sets strict rules to protect the interests of all parties involved, including advertisers who are often harmed by the improper actions of site owners who are members of the AdSense program.
Some Google sites that must be adhered to by the website or blog owner of the AdSense program participants are:
Clicking on ads that appear on their own site, either manually or with the help of special software. Intentionally encourages site visitors to click on the displayed ad, for example with the words "click this ad" or "visit this page"
Change the shape and size of a predefined ad unit Google Make a link directly to the AdSense search results page for search
Automatically fill the AdSense search box with certain keywords
Manipulate ad targets with hidden keywords or with IFRAME
The AdSense ad unit code must be placed directly in the HTML code of the Website without the ingredients. Site owners are not allowed to change the AdSense code for any reason, for example with the aim of displaying the results of a pop-up window or diverting the target ad.
AdSense Income Optimization
The potential benefits of joining the AdSense program make many website owners develop various methods to increase the number of clicks on the ads they display. Some methods prove illegal and fight the official AdSense program policies.
Other methods are allowed, even driven by Google. Some methods that are considered valid are:
Modify the ad unit color using the color palette provided by AdSense
Put ad units in certain positions on web pages that are considered to have a high level of readability
Remove the ad unit's edge and match the color to the Iatar color of the web page so that the ad unit appears to blend in with the contents of the page
Source: http://id.wikipedia.org/wiki/AdSense