diff --git a/yews/datasets/__init__.py b/yews/datasets/__init__.py
index 7d8aa68..6cf360c 100644
--- a/yews/datasets/__init__.py
+++ b/yews/datasets/__init__.py
@@ -1,9 +1,8 @@
 from .base import BaseDataset, PathDataset, is_dataset
-from .file import FileDataset, DatasetArray
-from .dir import DirDataset, DatasetFolder, DatasetArrayFolder
+from .files import FileDataset, DatasetArray
+from .dirs import DirDataset, DatasetFolder, DatasetArrayFolder
 
 __all__ = (
-    'is_dataset',
     'BaseDataset',
     'PathDataset',
     'FileDataset',
diff --git a/yews/datasets/dir.py b/yews/datasets/dirs.py
similarity index 92%
rename from yews/datasets/dir.py
rename to yews/datasets/dirs.py
index ce5f1e7..034d31f 100644
--- a/yews/datasets/dir.py
+++ b/yews/datasets/dirs.py
@@ -1,4 +1,11 @@
 from .base import PathDataset
+import numpy as np
+
+__all__ = [
+    'DirDataset',
+    'DatasetArrayFolder',
+    'DatasetFolder',
+]
 
 
 class DirDataset(PathDataset):
@@ -41,7 +48,7 @@ class DatasetArrayFolder(DirDataset):
 
     Attributes:
         samples (list): List of samples in the dataset.
-        targets (list): List of targets in teh dataset.
+        targets (list): List of targets in the dataset.
 
     """
 
@@ -92,16 +99,16 @@ def __init__(self, files, loader):
             self.loader = loader
 
         def __getitem__(self, index):
-            return self.loader(self.file_list[index])
+            return self.loader(self.files[index])
 
         def __len__(self):
-            return len(file_list)
+            return len(self.files)
 
     def __init__(self, loader, **kwargs):
-        super(DatasetFolder, self).__init__(**kwargs)
         self.loader = loader
+        super(DatasetFolder, self).__init__(**kwargs)
 
-    def make_dataset(self):
+    def build_dataset(self):
         files = [p for p in self.root.glob("**/*") if p.is_file()]
         labels = [p.name.split('.')[0] for p in files]
         samples = self.FilesLoader(files, self.loader)
diff --git a/yews/datasets/file.py b/yews/datasets/files.py
similarity index 96%
rename from yews/datasets/file.py
rename to yews/datasets/files.py
index 7801643..9da4681 100644
--- a/yews/datasets/file.py
+++ b/yews/datasets/files.py
@@ -3,6 +3,11 @@
 
 from .base import PathDataset
 
+__all__ = [
+    'FileDataset',
+    'DatasetArray',
+]
+
 
 class FileDataset(PathDataset):
     """An abstract class representing a Dataset in a file.