Default Bid for Adwords is the price which you are willing to pay in ad group level. For example, when you want to start a new ad group in a campaign, Adwords will always ask you to enter your default bid for your new ad group. This is because if you forget to add in bid price for a new keyword in the ad group, the default bid will come into play.
With the default bid running, you are sure to show your PPC ad for that particular keyword, unless it is below bid or you have paused the keyword.
You will need to choose the right keyword bid pricing individually for each keyword, in order to maximize the profit in your PPC campaigns. As using PPC is the same as in business, you must always remember two important elements that will guarantee your success. One is to do your best to increase sales, second is to do your best to cut down cost in your business.
I would also recommend that you position the default bid lower than all keywords in the ad group, as you will not pay have to for those keywords that are worth that much. This is the element of successful business using cost reduction.
Do you do the above strategies in your PPC marketing or use it in your business? Share with us what are the ways you use to promote your products or services using PPC. Hear from you soon, and I will reply you.