Google Account Structure
This diagram was created to try and explain the complexity of a Google Client Account. If you wish to use this on your website please contact me first.

Client Account
This is the top level of a Google Client Manager's account structure. Each client has their own billing agreement with Google.
Campaign
Each account may have up to 25 advertising campaigns. Campaigns may be targeted by location or language. You can schedule your ads to run at particular times and you can even adjust your maximum cost per click bidding to adjust pricing for your ads during certain time periods. Negative keywords can be set up at the Campaign level as well as the Keyword level.
Opting into the Content Network or Search Network is also set at the campaign level. See the Google Network page for more information on the various Google Networks. Maximum cost per click may be set here and also at the individual Keyword Level.
Running several campaigns allows advertisers to set up daily budgets for different sets of keywords. You can create one campaign to appear only on the search network, and a second campaign only for the content network.
Ad Group
Every campaign must have at least one and a maximum of 100 Ad Groups. This level allows ads to be grouped logically. Keywords are set up at the Ad Group level. How the adverts are shown is also set at the Ad Group level, the adverts may be evenly spread throughout the day or shown constantly until the daily budget is exhausted.
Adverts
Every Ad Group must have between 1 and 50 adverts. By creating multiple adverts advertisers can test the effectiveness of different text adverts within their advertising campaigns. Maximum cost per click may be set here
A standard text ad has the following format:
Line 1 35 characters
Line 2 35 characters
Display URL
Keywords
Each Ad Group may have up to 2000 keywords. These are the words visitors type in to the Google search pages. There are several different matching options available, please see the Keyword Matching page for more information.
As you can see from the diagram above, with up to 25 campaigns each with up to 100 Ad Groups comprising of up to 2000 keywords there can be up to 5,000,000 keywords associated with each account. This is why Hardington Consultancy has written a bespoke software program to manage our clients keywords (we do not use automated software to manage accounts, we use real people!). Sorry, the Keyword management software is NOT for sale!