what are the common methods of communication used in an organization and for what purposes are they used for?

Answer 1

I would have to say "Formal" and "Informal" come to mind for me. Formal communication is something that follows a specific path in the company. If you have a problem, you tell your boss; you don't go straight to the CEO or other senior executive. Up and down the chain of command and not across the organization. Meetings usually follow formal guidelines as well; the person who called the meeting is in control and should guide the rest of the meeting participants toward his/her goal.
Typically, a follow up is completed that gives all of the participants a summary of the meeting.

Informal is stopping by someone's desk to talk to them about a project or task you are working on. You get the information you need and move on. This can be done with anyone in the organization, including senior members that you wouldn't be likely to ask to attend a meeting, but you would like their feedback anyway. This can go up and down the chain of command or side to side across the organization.

Good Luck!

Answer 2

Verbal communication, including talking on the telephone, Non-verbal communications ie) body language, eye contact, silence. Minutes of meetings, reports, charts and e-mails...The list is endless.