php stream_context_create confusion

I know that this feature in php creates and returns a stream context with any options supplied in options preset. I also know that I can use it to do what I want which is to pass my username and password credentials...But I still don't quite get how to use this feature and what it exactly does the complicated words in the description are really confusing me....I have the code from the example but I don't know how I can use this feature to pass credentials to www.confluence.com (only I can access it since its on a apache server). Can someone please explain or give example of how I can use this to pass the credentials?

EDIT: Here is the overal summary, pretty short so dunno if you call it a summary....I am assigned an app to make.....there is about 10 different ways to do this. due to the limitations they have given me, I can only work with 1 way that I found...I am very frustrated because there is a much easier way to do this using google calendar but they refuse due to security reasons so I am stuck to confluence calendar.....In addition to that, to make this harder, confluence is hosted by external company and so I cannot even use get_contents to directly access the confluence calendar because it asks for login credentials....I am not a pro at this and one after another obstacles keep popping up to make my life harder and this is just bs...Ive spent hours and hours for the past 3 weeks finding solutions only to have it rejected...Ive finally got this get_contents thingy working but now login credentials is a pain in the butt and I have never dealt with this so I am trying my best but I have ABSOLUTELY NO IDEA what stream_context_create does OR how to even use it to pass my credentials...Confluence the site I am trying to access I can manually login using my logins but the code cannot....confluence is on an apache server开发者_如何学Go so other people cannot access it....and I cannot share my login info as that is company's security issue...I am sorry if i made no sense but I am very frustrated and can find no solution and my mind is half dead from coding and reading Believe me I have done much searching and googling....But Ive finally reached the point where I am blank stuck...

<?php
$opts = array(
  'http'=>array(
    'method'=>"GET",
    'header'=>"Accept-language: en\r\n" .
              "Cookie: foo=bar\r\n"
  )
);

$context = stream_context_create($opts);

/* Sends an http request to www.example.com
   with additional headers shown above */
$fp = fopen('http://www.example.com', 'r', false, $context);
fpassthru($fp);
fclose($fp);
?>

I found some additional code here similar to what I am doing but not quite sure what to do with this or how to modify it..

$data = array('account'=>'javier', 
              'password'=>'12345', 
              'submit'=>'SUBMIT'); 

$content = file_get_contents('http://localhost/misc/login.php', false, stream_context_create( array('http' => array('method' => 'POST', 'content' => http_build_query($data) ) ) ) ); 

$sFind = 'Logged in'; 
$search = strpos($content, $sFind); 

echo $content; 

if($search === false){ 
echo 'Invalid Account'; 
} 
else { 
echo 'Valid Account'; 
}  

Another Idea I have is to use JavaScript to do the login...I dont know which is better but I am not allowed to download any libraries or such so suggestions are nice.

You are using the 'GET' method, it is uncommon for login information to be passed like this. Are you sure the page you are requesting doesn't use POST?

Also personally when retrieving webpages, especially when sending POST or GET variables I prefer to use cURL.