diff --git a/models.py b/models.py
index fc48b46..dfe9c9e 100644
--- a/models.py
+++ b/models.py
@@ -1,6 +1,6 @@
 from sqlalchemy import (Column, DateTime, Integer, String, create_engine, func, )
 from sqlalchemy.ext.declarative import declarative_base
-from sqlalchemy.orm import sessionmaker
+from sqlalchemy.orm import sessionmaker #Что такое sqlalchemy и почему стоит точка orm?
 
 PG_DSN = 'postgresql://POSTGRES_USER:POSTGRES_PASSWORD@localhost:5432/POSTGRES_DB'
 engine = create_engine(PG_DSN)
@@ -8,8 +8,8 @@
 Session = sessionmaker(bind=engine)
 
 
-class AdModel(Base):
-    __tablename__ = 'advertisements'
+class AdModel(Base): #Что такое class? Почему в скобочках Base?
+    __tablename__ = 'advertisements' #Почему тут два нижних подчеркиваний?
 
     id = Column(Integer, primary_key=True)
     title = Column(String, index=True, nullable=False)
diff --git a/server.py b/server.py
index e9d2919..853d2d6 100644
--- a/server.py
+++ b/server.py
@@ -23,7 +23,7 @@ class CreateAdModel(pydantic.BaseModel):
     description: str
     owner: str
 
-    @pydantic.validator("title")
+    @pydantic.validator("title") #Что такое собачка? 
     def min_max_length(cls, value: str):
         if 1 > len(value) > 70:
             raise ValueError('Title should be from 1 to 70 characters')