Okay, so let's talk about PHP.
The first and the most important question is what's p.h.p.
Well, it is a server side programming language and it was designed for web development in mind.
Now these days it can be used as a general purpose programming language.
But that's not the case very often.
It is still mostly used for web development.
So PHP is open source, and this means that the PHP source code is publicly available for everyone to
see.
And you can also try and contribute to the PHP code.
PHP is cross-platform, it runs on any operating system and it has an extensive built in library.
Now the use cases of PHP.
So as I said, it's mostly used to create dynamic web pages for the server side programming and also
to create command line utilities.
So to give you an example of a command line utility, there is a tool called deployer which is used
to deploy PHP applications on remote Servers.
So there are different aspects of creating the PHP programs.
And actually you would have to understand them separately and some of them require more effort.
Others are just something you learn along the way.
So the first thing that will require your effort is learning the language itself.
So you need to understand the syntax, the data types, all the control structures that control the
flow of the programs.
Then there are functions and classes.
And how do you handle errors.
Now the runtime.
Well that's actually the environment in which the PHP programs you have created run.
So that's the execution process.
How are the PHP programs run?
You will have to eventually understand that.
How is the memory managed?
How does the garbage collection works.
So the runtime, that's a thing that will most probably come to you with experience.
It's not something that you can just learn or read about.
There are some things you should be aware of.
But as I've said, the understanding of the runtime and the environment, this always comes with experience.
The more programs you create and run, the more experience you will gain.
So the last aspect of understanding the PHP programs is how do you actually work with all the features?
So concepts like sessions, cookies, the file uploading, database interactions and handling web requests,
those are not things that are unique to PHP, but you just need to understand how do you work with all
those features using PHP as a language and PHP as a runtime or environment?
So PHP has some specific ways.
For example, sessions and cookies are handled using global variables and functions.
The database interactions.
Well, you might need to understand and use objects and classes for that, etc. etc..
So this is just understanding how you do all those things that are web development related using PHP
as a language and environment.