Many moons ago, taking Sociology 'A' Level, I learny about the different definitions of these two groups.
I hope it might be useful to consider where the main gender-stressing advocacy groups lie in relation to these two catagories.
This is roughly what I understood the definitions to be:
Interest Group:
Formally organized
Interest-oriented
May or may not influence the policies of the government
Softer in outlook
More or less protective:
Pressure Group:
Strictly structured
Pressure-focused
Must influence the policies of the government
Harsher in attitude
Protective and Promotive. www.quora.com/How-are-pressure-groups-and-interest-groups-different
The "Protective and Promotive' bit I understood to mean that interest groups were tending to look to the welfare of their people, whereas pressure groups were keen on promoting issues in ways that included increasing the numbers in their cohort, or example, by converting members of the public to their religion.
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