Will Javascript Take Over the World? | Brian Kernighan and Lex Fridman | Summary and Q&A

July 20, 2020
Lex Fridman
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Will Javascript Take Over the World? | Brian Kernighan and Lex Fridman


JavaScript, once considered an ugly and irregular language, has evolved and become efficient, leading to its increasing dominance in both backend and frontend development.

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Key Insights

  • 🌐 JavaScript Evolution: JavaScript was initially considered an ugly and unfit language for academics, but it has evolved into a viable solution for both front-end and back-end development due to improved language and compilation technology.
  • 📚 Leveraging Libraries: Unlike the past when programmers built everything from scratch, languages like JavaScript and Python rely heavily on libraries. While this allows for greater functionality, it also means downloading numerous packages with potential security and compatibility concerns.
  • 💡 Importance of Libraries: The abundance of libraries has made programming more efficient and convenient. However, the reliance on these libraries also poses challenges in terms of understanding, maintaining, and troubleshooting code, especially with the vast number of packages available.
  • ⚙️ Machine Learning Dependencies: When working with machine learning, downloading additional packages is necessary, often without knowing the details of what they contain. This lack of transparency can cause difficulties when troubleshooting or trying to ensure security within a project involving large downloads.
  • 💻 Collaboration and Building on Code: The world of programming now heavily emphasizes leveraging existing code and building on top of it. This collaborative approach allows for faster development but requires increased awareness of security vulnerabilities and potential compatibility issues.
  • 🔒 Security Concerns: The use of multiple libraries and packages without a thorough understanding of their workings can lead to security vulnerabilities. This is especially true in the JavaScript ecosystem, where the lack of discipline and control can increase the risk of security breaches.
  • 🌍 JavaScript's Influence: Although JavaScript is unlikely to fully dominate all programming languages, it continues to grow in significance, becoming a vital language for web development and potentially expanding into other fields in the future.
  • 💻 Becoming an Expert: The rapid pace of advancements in JavaScript and other languages makes it challenging to stay up-to-date and acquire expertise. Constant learning and experimentation are necessary to keep pace with new developments and understand the ever-expanding library landscape.


so what do you think about another language of JavaScript that's this well let me just sort of comment on what I said when I was brought up sort of JavaScript pasina's the probably like the ugliest language possible and yet it's quite arguably quite possibly taking over not just a fun in the backend of the internet but possibly in the future taking... Read More

Questions & Answers

Q: How has JavaScript evolved over time and what factors have contributed to its increasing dominance in development?

JavaScript has undergone significant improvements, both in its language features and the technology used to compile it. These advancements have made it more efficient and viable for different types of development, leading to its widespread adoption in backend and frontend development.

Q: How does the use of libraries in JavaScript and Python differ from the earlier days of programming in UNIX and C?

In the past, programmers had to build everything from scratch, resulting in a more hands-on experience. However, with the rise of JavaScript and Python, developers now rely heavily on libraries to expedite development. While leveraging libraries offers convenience, it can also introduce complexities and dependencies, making it important to carefully manage and understand the code being utilized.

Q: What challenges can arise from the widespread use of libraries in programming languages like JavaScript and Python?

The extensive use of libraries in modern programming can lead to challenges such as dependency management, security vulnerabilities, and limited understanding of the underlying code. Large numbers of libraries need to be downloaded, which can make it difficult to track their origins or ensure their quality and security, potentially leading to unstable or unsafe codebases.

Q: Is there a concern regarding the lack of control and potential security risks in the JavaScript ecosystem?

Yes, the JavaScript ecosystem, particularly in the NPM environment, has been criticized for its lack of control, discipline, and potential security issues. The vast number of packages and lack of transparency can make it challenging to ensure the reliability and security of the code being utilized. Therefore, it is not advisable to use JavaScript for critical applications like running a nuclear power plant.


In this video, the speaker discusses the evolution of JavaScript and its widespread usage. They also touch upon the concept of leveraging libraries in programming languages like Python and JavaScript. The speaker expresses concerns about the increasing number of libraries and the lack of control and security in the process.

Questions & Answers

Q: What is your opinion on the evolution and current state of JavaScript?

Well, I think you've captured it in a lot of ways. When Javascript was first introduced, it was considered to be an ugly and irregular language. It wasn't deemed suitable for academic use, and people would ridicule those working on JavaScript. However, over time, the language itself has evolved, and the technology for compiling it has improved significantly. Consequently, JavaScript has become a viable solution not only for backends but also for front-end development. Personally, I find it to be a pretty good language, though I'm not an expert. Keeping up with all the new developments can be challenging, but JavaScript has certainly become an important language in the tech industry.

Q: In contrast to the earlier days of programming, where building from scratch was common, modern programming often involves leveraging libraries. What are your thoughts on this trend?

That's a very perceptive question. Indeed, one of the reasons programming used to be fun in the past was because you had to build everything from scratch. The number of libraries one had to deal with was relatively small, such as standard libraries or printf. However, in the present day, this is not the case. When working with languages like Python and JavaScript, you often have to download numerous external libraries to accomplish your goals. Unfortunately, this adds a level of uncertainty, as you have little control over what these libraries contain. For example, while experimenting with machine learning, I've encountered situations where I needed to install additional packages without knowing exactly what they contained. This lack of transparency and control is even worse in the JavaScript ecosystem, specifically with the NPM (Node Package Manager) environment, as there seems to be less discipline and governance. Apart from the risk of not understanding how these libraries work, there are also security concerns. Ultimately, relying heavily on libraries can be problematic, and I wouldn't recommend using JavaScript for critical applications, such as running a nuclear power plant.

Q: Do you believe JavaScript will take over the programming world?

While JavaScript has become an important and widely used language, I don't believe it will completely take over the programming world. It certainly has a significant presence on the internet, both on the front-end and back-ends of applications. However, the programming landscape is diverse, with various languages and technologies serving different purposes. JavaScript's rise in popularity shouldn't overshadow the existence and relevance of other languages. Therefore, while JavaScript is undoubtedly a significant language, I believe its dominance will be limited to specific domains rather than taking over everything.

Q: How would you compare the experience of programming with libraries to programming from scratch in the Unix and C days?

The experience of programming with libraries today is vastly different from the early days of Unix and C. In the past, developers had to create everything themselves, and the number of libraries one had to deal with was minimal. For instance, you might have just used printf or the standard library. This allowed for a more hands-on and holistic approach to programming. In contrast, modern programming with languages like Python and JavaScript involves extensively leveraging libraries to build upon existing code. While this can be convenient and time-saving, it also introduces complexities and uncertainties. Downloading and using libraries often means relying on code written by others, which leads to a loss of control and a lack of understanding of what is happening under the hood. This paradigm shift in programming has its advantages, particularly in terms of productivity and speed. However, it's important to recognize the trade-offs and potential drawbacks associated with heavy library usage.

Q: Are there any specific challenges or concerns you have with the usage of libraries in modern programming languages?

Yes, there are several challenges and concerns associated with the usage of libraries. First and foremost is the issue of control. When relying heavily on external libraries, you are essentially placing trust in other developers' code without thoroughly understanding its inner workings. This lack of control can be disconcerting, especially in critical applications where reliability and security are paramount. Additionally, the ever-increasing number of libraries available for programming languages like Python and JavaScript makes it challenging to evaluate and choose the right ones. It's not uncommon to download multiple libraries without truly knowing their quality or level of maintenance. This lack of transparency also gives rise to potential security vulnerabilities. Lastly, the sheer dependency on libraries can create challenges in terms of troubleshooting and debugging. When something goes wrong, it becomes more difficult to pinpoint the root cause among a web of interconnected libraries. Overall, while libraries offer a wealth of resources and functionality, their usage should be approached with caution and careful consideration.

Q: How do you perceive the impact of libraries on the overall programming experience?

The impact of libraries on the programming experience is dual-sided. On one hand, libraries greatly enhance productivity and development speed. They allow developers to build on existing code and reuse established solutions, saving time and effort in development. Libraries can provide complex functionalities or domain-specific capabilities that would otherwise require substantial expertise and development effort. On the other hand, heavy reliance on libraries may lead to a certain level of dependency and a potential decrease in understanding the underlying concepts. It's crucial for developers to strike a balance when using libraries, making sure they maintain a good understanding of the core concepts and algorithms and not just relying blindly on the libraries' functionalities. Ultimately, libraries can be powerful tools, but they should be used mindfully, with a clear understanding of their implications.

Q: Is there a possibility of libraries becoming a hindrance in the programming process?

Yes, there is a possibility that libraries can become a hindrance in the programming process. As the number of libraries grows, the complexity of managing dependencies and ensuring compatibility increases. This can lead to situations where using multiple libraries becomes challenging and sometimes problematic. Compatibility issues may arise when different libraries rely on conflicting versions of underlying dependencies, leading to errors and difficulties in integration. Additionally, the lack of control and transparency in library usage can make troubleshooting and debugging more challenging. When something goes wrong, it can be difficult to isolate the issue within the web of interconnected libraries. Therefore, while libraries can undoubtedly enhance productivity, developers need to be mindful of potential roadblocks and plan accordingly to mitigate any hindrances that may arise.

Q: In your opinion, what are the main differences between the old days of programming and the modern approach of leveraging libraries?

The main differences between the old days of programming and the modern approach of leveraging libraries lie in the development process and the resulting codebase. In the past, programming was a more individualistic endeavor, where developers had to create everything from scratch. This required a deep understanding of the underlying concepts and a meticulous attention to detail. On the other hand, modern programming with libraries allows developers to build upon existing code and reuse established solutions. This shift has significantly increased productivity and reduced the time required to develop complex functionalities. However, it also introduces new challenges, such as managing and evaluating libraries, dealing with compatibility issues, and maintaining control and understanding of the entire codebase. The use of libraries has made software development more accessible and efficient while simultaneously adding layers of complexity that require careful management.

Q: Can you elaborate on the security concerns associated with relying on external libraries?

Relying on external libraries introduces a certain level of risk and security concerns. Firstly, you are trusting the developers behind those libraries to follow secure coding practices and thoroughly test their code. However, this isn't always the case, as the sheer number of libraries available makes it difficult to ensure each one's quality and security. Vulnerabilities or weaknesses in a library can propagate to the applications that utilize it, potentially exposing them to security threats. Secondly, the lack of control and understanding of the specific functionalities implemented in each library makes it challenging to thoroughly analyze the security implications. A library may inadvertently introduce security flaws, leaving the developers and users unaware until a vulnerability is exploited. Lastly, the dependency tree created by using multiple libraries increases the attack surface. If a single library within the chain is compromised, it can have a domino effect, affecting all the applications that depend on it. Therefore, it is crucial to carefully vet and monitor the security posture of the libraries used, as well as staying updated with potential security patches and updates.

Q: What are your thoughts on the potential impact of leveraging libraries on code maintainability?

Leveraging libraries in programming can have both positive and negative impacts on code maintainability. On one hand, libraries offer the advantage of reusing existing and well-tested code, reducing the effort required to develop and maintain complex functionalities. This can lead to increased code maintainability, as developers can focus on the core logic of their applications rather than re-implementing established solutions. However, heavy reliance on libraries also introduces challenges. It's essential to stay up-to-date with library updates and patches to ensure compatibility and address security vulnerabilities. Additionally, libraries themselves may have dependencies that require management, adding complexity to the codebase. Over time, the accumulation of numerous libraries and their associated dependencies can make code maintenance more challenging. Developers need to strike a balance between leveraging libraries for increased productivity and maintaining a manageable and sustainable codebase.


The evolution of JavaScript has seen it transform into a widely used and important language, both in the front-end and back-end of web development. Despite its initial reputation as an ugly and irregular language, significant improvements in the language itself and the technology surrounding it have made JavaScript a viable solution for various use cases. However, the reliance on external libraries in programming languages like JavaScript and Python has introduced complexities and concerns. The abundance of libraries makes it challenging to assess their quality and security, and the lack of control and understanding can be problematic in critical applications. Properly evaluating and managing libraries is crucial to minimize risks and ensure maintainable code. While libraries offer productivity gains, developers should approach their usage carefully, striking a balance between leveraging existing solutions and maintaining control, understanding, and security in their codebase.

Summary & Key Takeaways

  • JavaScript was initially considered an ugly and irregular language, but it has evolved over time and become more efficient.

  • It is now a viable solution for backend development and a widely used language for frontend development.

  • The use of libraries in languages like JavaScript and Python has changed the programming experience, allowing developers to leverage pre-built code for faster development, but it also introduces challenges and potential security risks.

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