In the 20th century, digital technology was finally developed, and the first electronic calculating machines were produced. It was the task of pioneers in computing to translate numbers and letters into a system which computers could understand. Binary code was made for this since the abstractions of 1s and 0s can be translated into physical states. For example, in electrical engineering, you can use 1 if there is voltage and 0 if there is no voltage.
Punch cards also use a binary system to communicate information. These cards can represent a certain number of characters using a hole or a lack of a hole. This allows information to be stored permanently and still be machine readable. Punch cards were already being used before computers were invented, such as with looms and mechanical music machines.
At first glance, binary code and binary system seem to be synonymous. However, once you understand what a code is, you will see the difference. A code is the controlled translation of characters. Each character in the original is assigned a different character or character string. This makes it possible to convert back and forth. Meanwhile, a system is self-contained and does not need to be compared to another system. For example, if you are computing using the binary system, you do not need to refer to the decimal system to get results.
Both can be found in electronic data processing (EDP). For example, this coding can be found in ASCII code. All letters in the Latin alphabet as well as some other characters can be represented with seven positions and two states (1 and 0). However, since this cannot represent anywhere near all the characters in the world, you can also use UTF-8 which uses one to four 8-bit bytes.