In addition, some of the materials used in IQ tests may be totally foreign to certain cultures, thus creating inequalities and biases. It is interesting to note that IQ scores have increased so much over the 20th century that most of today's test takers would be considered 'geniuses' by 1900 standards.
Digital subscriber line (DSL; originally digital subscriber loop) is a family of technologies that are used to transmit digital data over telephone lines.
A DSL line can carry both data and voice signals and the data part of the line is continuously connected. Digital Subscriber Line technology assumes that digital data does not require change into analog form and back. Digital data is transmitted to the system directly in digital data form, allowing wider bandwidth for transmission.