Computer Science techniques are becoming increasingly important to all other disciplines. On the other hand, inputs of other disciplines is becoming increasingly important for problem solving even in those situations where apparently, we are using computing and related techniques to solve problems. Recognizing this, several leading universities in the world are working on what they call a "CS + X" strategy. While the research component of "CS + X" has been visible for some years now, with several joint conferences and sponsored research projects in inter-disciplinary and multi-disciplinary areas, it is only recently that the teaching programs under this strategy are starting to be offered.
Stanford University has been offering several "Joint Major" programs under "CS + X" initiative since 2014 Fall. However, the offerings are restricted to only a few disciplines in Arts and Humanities.
University of Illinois at Urbana-Champaign has a bit more diverse set of offerings under its "CS + X" initiative and one can take a joint major of Computer Science with music, anthropology, chemistry, astronomy and a few more.
Northwestern University has its own "CS + X" strategy though I could not find any teaching program offering on its website.
It may be noted that a lot of universities have one or two programs which involves inputs from Computer Science and one or two other departments. Typical examples are Maths and Computer Science, or Design and Computer Science, or Art/Film/Theatre/Media and Computer Science. When a university has only 1 or 2 such programs, it is done on a case to case basis, and there is no overarching strategy or principle to replicate such programs with other departments. In such cases, we assume that they do not have a "CS + X" strategy.
In India, the only institute which has a well thought of "CS + X" strategy is IIIT Delhi. The thought process started in 2015 when the construction for Phase 2 of the campus infrastructure started. The expansion of the infrastructure was to take care of a student population more than 2.5 times the population at that time. There was a lot of discussion on whether the increase should simply be in the CSE and ECE programs that were going strong at that time, or should there be a diversification in our offering. A lot of people from within India and outside, including people from academia and industry, were consulted. A few workshops were held, and finally it was decided that most of the increase in admission will be through "CS + X" strategy. It was felt that students have or develop different interests and one size fit all will not meet their aspirations. On the other hand, even industry is looking for talent which is different from plain vanilla computer science.
The first program to start in 2016 was Computer Science and Applied Mathematics. Then in 2017, two more programs were started Computer Science and Design, and Computer Science and Social Science (named then as IT and SS). In 2018, yet another program is being started, Computer Science and BioSciences.
To understand these programs, one has to understand different types of offerings that universities have when someone wants to study two different disciplines in an undergraduate program.
Studying two disciplines is possible in the following different ways (not all universities offer all options):
Dual Degree: This is the most comprehensive study of both disciplines. You complete all graduation requirements of Bachelors in 'X' and all graduation requirements of Bachelors in 'Y'. Assuming that bachelors in 'X' requires around 40 courses, and bachelors in 'Y' requires around 40 courses, the total requirement will not be 80 courses, but may be around 48-50 courses. This is because all common requirements need to be finished only once. Also, courses in 'X' may count towards open elective requirements of degree in 'Y' and vice versa. Such a program can be easily completed in 5 years (assuming that both bachelors programs have a normal duration of 4 years).
Second Major (Or double major): In these programs you complete the degree requirements of discipline 'X' and do many courses (8-10) of discipline 'Y'. You do not need to complete all graduation requirements of a bachelors degree in 'Y' which could include may be around 15 courses in the discipline and perhaps some breadth requirement as well. These 8-10 extra courses can be taken in the open elective slots of the degree program in 'X'. And depending on how many slots are available, one may need to take up only 1 or 2 additional courses. So overall you will do 40-42 courses and can normally complete this within the normal duration of the degree in 'X'.
Minor: In these programs, you complete all degree requirements of discipline 'X' and do only a few courses (4-5) of discipline 'Y'. Since any good program in 'X' would have at least that many open elective slots, this can certainly be done within the normal duration of the program.
Joint Major (or joint degree): This is the approach taken by "CS + X" initiatives. In joint major, you look at the graduation requirements of discipline 'X' and remove some advanced courses and final year electives. Similarly, you do the same for discipline 'Y'. So overall, you bring down the graduation requirements to 40-42, similar to a single degree requirements. But you may have less elective slots now. In addition, you may have a few specialized courses which have inputs from both disciplines. You may be additionally required to do your final year project in a way that it requires skills and knowledge from both disciplines. Normally, one is being prepared for a niche inter-disciplinary world, but the program is structured in a way that one can go for Master's program in either discipline 'X' or discipline 'Y'.
The world over, students are increasingly studying two disciplines in their undergraduate programs. While the number of dual degrees and joint majors is very small, the number of students opting to do a second major or a minor is very high. I can see why dual degree did not become popular - it was taking more time which meant not only higher college costs (an additional year of tuition and living) but also joining workplace a year later. But this new trend of joint majors takes care of that issue, and I am convinced that the future of joint major programs is very bright.
So, if you are a 12th class student, looking for options to do engineering, do consider the "CS + X" offerings of IIIT Delhi.