Here is an example of the Steam GetPlayerSummaries api in work with PHP. I have made a function called summary that creates an array with the data so i can call it once and get many or all data values from it. As its in a function i can put it in an include file and keep my main workpage tidy.

function summary($steamid)
{
    $data = json_decode(file_get_contents("https://api.steampowered.com/ISteamUser/GetPlayerSummaries/v0002/?key=YOURAPIKEY&steamids=" . $steamid . ""));
    $main = $data->response->players[0];//go through through the array
    $profile_state = $main->profilestate;
    $name = $main->personaname;
    $lastlogoff = $main->lastlogoff;
    $profileurl = $main->profileurl;
    $personastate = $main->personastate;
    $realname = $main->realname;
    $timecreated = $main->timecreated;
    $loccountrycode = $main->loccountrycode;
    $avatar = $main->avatarfull;
    $created_on = date("Y-m-d\TH:i:s", $timecreated);
    $llo = date("Y-m-d\TH:i:s", $lastlogoff);
    return array('profile_state' => $profile_state, 'name' => $name, 'lastlogoff' => $lastlogoff, 'llo' => $llo, 'profileurl' => $profileurl, 'personastate' => $personastate, 'realname' => $realname, 'timecreated' => $timecreated, 'created_date' => $created_on, 'avatar' => $avatar);
}

$profile_data = sum('76561198045053248');
echo $profile_data['name'];//Speedy