Fatal error exception in routes.php (works fine in windows, messes up in linux)

I have this project made for my final semester to demonstrate concepts from Advanced OS coursework. upon serving on command line, GUI is visible on browser. However, a functionality cannot be reached on it. Upon hitting it, I see this on the webpage. "

Whoops, looks like something went wrong.
1/1 FatalErrorException in routes.php line 27: Class 'App\Items' not found

" . I am enclosing the code in my routes.php for reference.`

<?php

/*
|--------------------------------------------------------------------------
| Application Routes
|--------------------------------------------------------------------------
|
| Here is where you can register all of the routes for an application.
| It's a breeze. Simply tell Laravel the URIs it should respond to
| and give it the controller to call when that URI is requested.
|
*/

Route::get('/', function () {
    return view('welcome');
});

Route::get('postitem', function () {
    return view('postitem');
});
Route::auth();

Route::get('/home', 'HomeController@index');
Route::post('/itemPosted', 'HomeController@postItem');
//Route::post('/itemPosted', 'HomeController@searchItem');
Route::get('searchItem', function () {
    $item = App\Items::all();
    $data = array(
        'items' => $item
        );
    return view('searchItem',$data);
});
Route::get('bidnow', function () {
    return view('bidnow');
});
Route::post('/bidDone', 'HomeController@bidDone');`

via Chebli Mohamed