How to Become Expert

I am not sure what others saying, but here is my advice. I have developed million lines of code in PHP...I have developed many complex custom site like social sites from scratch. So there are two major ways to become an expert:

1- Freelancer
You must know php and MySQL very well as you end up doing lots of customization. Each client's requirement is different, so you should know it very well. I read 8 books on PHP to handle every tough customization. PHP cookbooks are great source for all freelancers. For instance, below is good article on MySQL coding. I read 4 books in MySQL.
https://blockchain.dcwebmakers.com/blog/...-ways.html


2- Senior developer
You must specialize mostly in one language like PHP...So getting a certification pays off well here.

For both tracks, you must know Object-Oriented Programming very well.

Lastly, nowadays most of back-end developers are ending up doing some work with Linux OS. So it is good to learn it. If you like to do any system admin job in Linux, you MUST know how Linux file system works. Almost half of Linux problems and troubleshooting issues can be fixed if you can visualize the Linux file system structural or architecture. Here is a great resource for learning it in depth:

https://coding-bootcamps.com/linux/files...eward.html


Lastly, it is a never ending journey of learning. I teach coding and sometime write tutorials. It helps me to learn the topic better. Also, all online and in person training classes would not be enough as they just scratch the surface...you need to buy and read hands-on advance books to really master it. It is not going to happen over night, it takes lots of time & efforts to call yourself an expert.