Hi There,
Firstly did not get the meaning of the question, " Things advertising includes"???.
I can only throw light that advertising is a means of communication.
A form of communication between the seller ( manufacturer) and buyer ( we people).

Advertising needs to be creative and at the same time appealing to the eyes of the viewer. They need to be realistic as masses are now well educated.
As an Advertising person, you need to know your subject very well. Knowledge of what is in demand is important. At the same time, knowing the product you wish to advertise, also must be well known.

Last but not the least, advertising must includes 3 major styles that appeal the masses. and they can relate to the product later on.

1. A catchy tag line. eg " No one can eat just one". Seeing this tag line just once anywhere reminds audience of Lays, even if they do not see the advertisement everytime
2. Musical Note. eg " Ting ting ting", reminds you of Good day biscuits
3. The PR used to promote the product. eg. Amitabh Bacchan reminds you of Cadbury.
   
   In terms of making a career in advertising, after 12th, one can pursue Mass media ( BMM), a 3 years under graduate course. Here in the last year one can specialise in Advertising.
   Also there are PG Diploma programs available in Advertising one can pursue.

But most important aspect in this field is the sense of visualization and being knowledgeable, rather aware of the masses.
Also hands on experience plays more importance in this profession.
Apart from your degree, get certified with Coral draw, Graphics, Web Designing etc

Hope this helps.
Wish you good luck....