You will often use knowledge such as linear algebra and probability theory. Later, I will study numerical analysis, mathematical experiments and write Matlab to solve mathematical problems. In the future, many applications will use the matrix calculation of line generation, and it will be much deeper than what you have learned, especially big data. For example, the wiring of a chip, the voltage of each point, and the Intel chip have all passed the knowledge of line generation, and they are stored in sparse matrix, and there are tens of meters of data, which can't be stored by a computer without compression, let alone the calculation of sparse matrix. Very advanced calculation methods must be used, otherwise even a powerful computer can't calculate it. For example, search engines judge users' preferences and intentions, and knowledge networks are also a huge matrix. Baidu search is not more than giving you a page. How can it be compared? It's all matrix calculations, and now there's AI in it. You can't handle this with a multiplication and division method. I can't play without a little knowledge of line generation. If you are engaged in AI, you need more mathematical knowledge.
Database is a way to store a large amount of data, because there is too much data. You can try to randomly search for a file in your computer, which may take several seconds. But web servers, such as Baidu Cloud Disk, have so many files, how can you get what you want out in dozens of milliseconds? You can't save files in your normal way, you must use the database. Including other things, such as answering questions that Baidu knows. The questions I answered were mixed with what tens of thousands of people answered today and put on the computer. You want to see this answer, how long does it take to search one by one? Database is to manage data timely and effectively.
Mapreduce is a framework, not a language. A framework means that it provides a lot of code written by itself, such as functions, classes and so on. You can use it. It is very convenient to use. Otherwise, you must write all this code yourself. Web pages are not written from scratch, but have a framework. Someone else wrote the framework, and you stand on the shoulders of giants and continue to write your code. In the open source era, many things are made by others, so you just need to write on them. So learn new things and new frameworks, and learn to search, otherwise every line of code is written by yourself, which is much less efficient than others.
Front-end and back-end are terms of network platform. The page you see has two pieces of code: one runs in your browser, usually js, called the front end, responding to your every click; The other piece is on the server, for example, Baidu knows that it runs on the server of Baidu House, which is called the backend. The language can be js or python. There are many of these two, and others can be used, or C. The front end is only responsible for presentation. After answering the question, I pressed the button. The front-end code of my browser will send my language to the server along the network cable, and the back-end code will be received and stored in the server. When you see this answer, the front-end code of your browser will send a request to that server along the network cable, and the server will send you my answer along the network cable, and then your front-end code will be displayed on your screen. That's it. So front-end and back-end are two completely different technologies, both of which have great knowledge. The front end is mainly about how to realize all kinds of cool or easy-to-use functions, buttons and so on. The back end is mainly a database, which is safe and resistant to pressure. The technology is very different, which often requires two programmers to write separately. Why are full-stack engineers so powerful? He can write front-end and back-end by himself. If a company hires one, it is equivalent to hiring two people.
So learn more. The more skills you learn, the higher your salary will be.
It's not a fancy game. Even if you open Unity and import some 3D materials, you can make a CS-like game in half a day. The code is still amazing. Code is probably the only world created by human beings. You are the creator of it. You can decide everything and play freely. It is also an extension of your thinking. You can use computers to calculate things that humans can't. This is the only pure land that is not disturbed by the world. It is worth cherishing and exploring.