Variables Video Lecture | PHP for beginners - Software Development

hello YouTube welcome to tutorial number
five in the PHP tutorial series and in
this video we're going to cover
variables we're gonna cover what they
are what they're useful and how to
create one okay so if you are new to
programming then a variable is pretty
much a way of storing a value and with a
variable you can use that value over and
over again in a script so it saves you a
lot of time so I can get out and you can
also use the value you know it's hard to
explain actually before you actually do
it
so if you've never programmed before
when you learn about variables you'll
think this is the biggest waste of time
ever it's pretty much like algebra in
school but then if you actually look
into it you know when you start writing
scripts you will realize that every
single script you write you'll use
variables all over the place so today
we're going to learn how to create a
string and an integer but if you have
previous periods with P it started with
them
programming and you know about variables
then you'll know in many languages you
have to actually set the data type of
the variable but in PHP we don't even
have to set that in PHP you just set the
value and it will automatically assign
the datatype so you don't have to set
like as a string as an integer PHP will
do that for us so as always we'll start
out with our PHP opening and closing
browsers PHP right there and then
another one there so we've now got our
file let's just save that as variables
dot PHP okay and we're just going to get
right into it and I'll just explain how
to make a variable now the first thing
you need to do is put the dollar sign
the dollar sign it will start it will be
the name of the variable so whatever you
type after this dollar sign that'll be
the name of the variable so I'm just
gonna call my variable name because I'm
gonna use my first name then put a space
and after the space she needs body equal
sign and that's gonna say to PHP that
we're gonna assign this variable to this
value are after the equal sign and as
with the echo function
we'll wrap your value in quotations so
we'll put double quotations and we're
going to type I'm Kris 5s name and after
that you know we have our semicolons and
the code so if we press save right now
and then just load tutorials for slash
variables dot PHP we can see there's no
errors and that means it's all away
correctly so let's go back and let's use
this in actual and I'll put and get to
the browser so we're going to do is use
the echo function once again if you
remember from the previous tutorial I'm
just going to say my name is and the way
to use a variable inside when you're
outputting data all you do is use the
name of the variable so dollar sign name
then close quotations semicolon hit save
and if you reload this it says my name
is Chris so what would actually doing
here is we're pulling this string data
from here from this variable and using
it here so we can also create an integer
because this right now is a string to
create an integer yet we just I'm going
to make a new variable
so again dollar sign name of the video
is going to be age and then equals and
the H is 18 and then have another space
and a semicolon so input my name is name
and I am and then dollar sign age years
old and if we hit save and it says right
there my name is Chris I'm 18 years old
so we can see that our variables are
working inside of the echo so what I'm
gonna do now just go over some rules of
variables there are rules when it comes
to variables and one is that a variable
name can only start with a on the score
or a letter so you cannot start
variables with a number so let's try and
do it down here I'm gonna call this one
variable equals we'll set that to test
and if we save that we should have an
error for line six it go unexpected TL
number and that's because you cannot
start variables with a number
and also you you can't have spaces in
the name available solely Craig Hollis
fast space name equals Chris and then
we'll say that oops
we'll save that reload and we have
another error on line six so what we can
do for this is user underscore so if we
just delete this and then we type fast
on the score name equals Chris and then
we'll make another one last underscore
name equals Johnson and then have this
semicolon and we can put my name is
actually will delete this and just write
it all again what echo sorry quotations
my name is and then first on the scroll
name and after that we're going to
choose last on the score name and then
we'll have a semicolon hit save and that
should work my name is Chris Johnson so
in this tutorial we've covered how to
create a integer and a string variable
and use them to output them to the
browser but what we can also do is use
single quotations as us just these two
right here well that will create
problems as we have to concatenate the
variables now don't worry about that
right now because I don't feel a lot in
this stage of the tutorials we need to
cover that I will make a video on that
soon about concatenation and using
single quotation variables because
actually very useful when doing HTML
because if you have like a href equals
and then double quotations to set the
link then you know that it's gonna trick
the PHP into thinking that you've ended
the actual string but don't worry about
that now
Purusha maybe even mention that but yeah
that is the end of this tutorial thank
you for watching so to pretty much sum
up what we've learned in this to create
a variable you're going to just hop
after take the dollar sign and then the
name of the variable and then an equal
sign and then in quotations or if it's
an integer you need to type the value
and after that obviously the semicolon
answer reference a variable when you're
asking
at home get out all you need to do is
use the variable name so if you have any
questions just leave comments or send me
a PM and please like the video and
subscribe to the channel peace