General and specific knowledge

How do you decide which framework, library or programming language you should learn next? And how do you make a decision between two similar things, for example: React or Vue.js? One criteria which can help making these decisions is figuring out how much of the knowledge required to learn a tool is general and how much of it is specific.

#Specific knowledge

Specific knowledge is knowledge that you need to learn to use a tool, but won’t be applicable outside of it.

The more you have of it, the more problems you can solve with that specific tool and the more it will increase your speed of development with that tool.

One example for specific knowledge is the syntax of a templating language. Here are examples showing some different ones:

#Template example: Handlebars

  {{#each people}}

#Template example: Svelte.js

  {#each items as item}

#Template example: Vue.js

  <li v-for="person in people">
    {{ person }}

These examples show that the syntax for a common problem like iterating over an array is different for each of them. Learning one syntax won’t help doing the same in a different one.

Additionally the more requirements you have regarding this problem, the more differences you will find. Each one has a different syntax for accessing the index of the current element, render based on conditions or filtering the array. The concept is the same, but the way to do it is different.

Now you might ask: Which one is the best?

My answer is: none of them. In this specific case the decision is subjective, so it doesn’t really matter.

I do think that there is a different and better solution to this problem though, and it has something to do with general knowledge.

#General knowledge

General knowledge is knowledge, which you need to learn to use a tool, that can be applied in other situations as well, e.g. different frameworks, libraries and even programming languages. It is reusable.

Let’s go back to the template syntax example. There is another quite popular tool called React, which has the following way to iterate over an array:

#Template syntax: React

  { =>

There is still some specific syntax knowledge here: how JSX works and when to add the curly brackets. Apart from this though, iterating over a list in React means using

Learning how to use this function will be helpful whenever you need to write code which works with arrays. It will be useful in other frameworks, in other programming languages and can even be a first step towards learning more about functional programming, which is again general knowledge.

This is the great thing about general knowledge and it’s what people mean when saying: “learning React, means learning JavaScript”.

The more general knowledge you have, the quicker you will understand other previously unknown areas of programming.

Choosing tools which mostly require general knowledge will allow you onboard your colleagues faster, because they might know most things already. It will also reduce the amount of maintenance, since general knowledge most often is based on standards/specifications and therefore less likely to change.

There is a much higher chance that a single framework/library author who came up with a new way of doing something, releases a breaking change, than that a specification changes. Additionally when a new version of a specification is created, a lot of effort is spent to maintain backwards compatibility with the previous one.

Software which relies on specifications is software which relies on agreement. People spent a lot of time to come up with solutions for general problems. Then they have agreed upon them and formulated a specification, which ended up in programming languages or other tools.

Note: I chose React as an example, because it is very popular and a lot of people know it. This doesn’t mean it generally is the best tool for this example. A tool like hyperapp-html uses even more general knowledge to iterate over a list:

#Example: hyperapp

    (person) => li(person)

Except for the order of function parameters, there is no specific knowledge here. The rest is JavaScript’s native syntax (or any other C style language) for function calls.

#Build upon general knowledge

If you create a new library, framework or programming language, think about how much specific knowledge you introduce with your tool.

Is it possible to build on top of agreements and use concepts that people already know? The more you reduce the amount of specific knowledge, the faster people will be able to learn and use that thing you are building.

This is not always possible, especially when tackling very new problems, but maybe there are parts of it, which don’t need to reinvent the wheel. Or maybe reinventing solutions accidentally created half-baked solutions compared to existing standardised ones.


The ratio of general and specific knowledge required by tools differs. Some require more specific knowledge, some require less.

Specific knowledge is neither bad nor good. It can be valuable when the tool allows you to solve a completely new problem for example or when it also teaches some general knowledge in other areas.

This shouldn’t be the only criteria when evaluating which tool to learn or use next, but it should be one of them.

If every criteria is quite equal and the choice is between general vs specific knowledge, I recommend to learn the tool which builds upon general knowledge. Because it’s based on specifications, it’s not only easier to learn for you and your colleagues, but it’s also more reliable and requires less maintenance in the future.

General knowledge will help you for the rest of your career.