I dislike the term "Third World" country. It's too generalised. I prefer to divide countries by economic development using these categories: Developed (read: industrialised), Semi-developed, developing and under developed.
Each country classified roughly based on GDP per capita, GDP nominal and overall living standards.
1) Mexico = semi-developed
2) Iran = developing
3) China = semi-developed
4) Venezuela = semi-developed
5) South Africa = semi-developed
6) Cuba = developing
7) Vietnam = developing
8) Turkey = developed
Each country classified roughly based on GDP per capita, GDP nominal and overall living standards.
1) Mexico = semi-developed
2) Iran = developing
3) China = semi-developed
4) Venezuela = semi-developed
5) South Africa = semi-developed
6) Cuba = developing
7) Vietnam = developing
8) Turkey = developed