What are the major social and economic changes that have occurred since the social theories written by Emile, Marx, and Weber?

Karl Marx and Max Weber were the leading proponents of a sociological way of looking at the world called social conflict theory. This theory holds that society is in constant conflict  because  of inequality between various groups and competition for limited resources. Marx held that it is not the way people think that determines their social existence but rather the reverse that is people social existence that determines how they think.  Weber argued that classes develop in capitalist societies where people compete for economic advantages.

The major change that has occurred since their theories in the 19th century is globalization.  Globalization refers to the world becoming one giant market economy with goods, capital and services being freely exchanged across national borders. Globalization leads to social inequality because only a select few , called the global elite, control most of the world's wealth. It leads to monopolies and oligopolies where wealth and power are unevenly distributed.  It also creates conflict because it espouses consumerism - the acquisition of goods - and since goods are limited people will end up competing for goods. This creates a culture where there are said to be 'winners'and 'losers'.