What is a modem and what are its uses?

a combined device for modulation and demodulation, for example, between the digital data of a computer and the analogue signal of a phone line. Basically, a modem is used to connect the analog world to the digital world. In other words, you can say it is the device that is used to convert the analog signal to digital signal

Explanation:

a modem is used for transmitting and receiving data over a communication channel, such as twisted-pair telephone lines, coaxial cables, and optical fibres.

Modem is short for "Modulator-Demodulator." It is a hardware component that allows a computer or another device, such as a router or switch, to connect to the Internet.

looking away, slouching, not focusing

explanation:

the major difference between the two is the objective and the reward of the game. candy crush has a puzzle theme with the objective of meeting a specific quota of points or objects, you are able to gain access to the next level and compete with peers on the process. on duolingo the objective is rather different, you are given sets of questions for you to answer for you to move to the next level and as for the reward, you are able to learn available language as this is an app developed to teach the user about other languages.