An informal group can be defined as one in which three or more people decide, perhaps on an ad hoc basis, to meet on a regular or semi-regular schedule for the purpose of discussing subjects of common interest, or for the purpose of engaging in a particular activity of common interest. It is contrasted by a formal group that has an established structure, possibly an agreed upon hierarchy involving "officers" (for example, president, vice president, treasurer, secretary, sergeant-at-arms, etc.), and possibly functions under agreed-upon rules designed to function professionally, like Roberts Rules that dictate the structure of the formal meeting to ensure fairness and a democratic process in the event votes are taken on whether to engage in a new type of activity or whether to merge with another group with overlapping interests.
Informal groups are not constrained by structures set forth in manuals like Roberts Rules of Order, and may or may not operate along democratic lines involving voting. In fact, depending upon the size and nature of the informal group's composition, voting may never be considered or required. Also, depending upon context, an informal group operating within a larger organization, like a business or agency structure, may exist for the sole purpose of allowing for informal, off-the-record discussions of ways in which to improve productivity of the organization or business, or it may be formed to allow for interactions among colleagues as part of a process of improving communications within the organization. Informal groups may simply exist to allow individuals with a shared passion for wine, mahjong, poker, politics, or virtually every other activity one can think of. The key characteristic of informal groups, though, is the absence of clearly delineated structures and rules dictating the group's conduct and activities, and much less emphasis on member turn-out for meetings. Informal groups are not likely to go through the motion that are an integral part of formal meetings like demanding the presence of a quorum before matters can be resolved.
Informal groups are social structures which connect people naturally over a period of time. In the business place informal groups can be seen as “cliques” of individuals who come together based on experiences they share in common. These groups determine how individuals relate with each other in the workplace and how they work. Members of a particular informal group may be seen to behave or even think in a similar way due to the influence, the individuals within the group have on each other. The relationship is of a friendly nature and is not bound by rules of official business hierarchies. Business organizations promote informal groups because they help break the monotony of the workplace by enhancing personal interactions. These personal interactions are beneficial to an organization because they foster fluid communication and help the members attain organizational goals.
Groups that come together due to a common interest or goals.
A group consist of two or more individuals who have come together to form a an interactive and interdependent relationship to achieve a particular group objective. Such groups may be formed as per the formal requirements of organizations such as businesses or other institutions. Such groups are defined by organizations structure and often characterized by designated role in the group work and nature of relationships between the group members. Such groups are called formal groups.
In contrast, informal groups are the groups that are neither formed in response to any organizational requirement nor have a formally defined structure of relationship between the group members. When an informal group adopts a formally defined structure and group processes, it no longer remains an informal group.