Ajax call    
$.ajax({
    url: "ajax_php_file.php", // Url to which the request is send
    type: "POST",             // Type of request to be send, called as method
    data: new FormData(this), // Data sent to server, a set of key/value pairs (i.e. form fields and values)
    contentType: false,       // The content type used when sending data to the server.
    cache: false,             // To unable request pages to be cached
    processData:false,        // To send DOMDocument or non processed data file it is set to false
    success: function(data)   // A function to be called if request succeeds
    {
    $('#loading').hide();
    $("#message").html(data);
    }
    });
php function
$sourcePath = $_FILES['file']['tmp_name'];       // Storing source path of the file in a variable
$targetPath = "upload/".$_FILES['file']['name']; // Target path where file is to be stored
move_uploaded_file($sourcePath,$targetPath) ;    // Moving Uploaded file