diff --git a/blog_project/blog/blog.db b/blog_project/blog/blog.db
index f63ad1b..ca922d3 100644
Binary files a/blog_project/blog/blog.db and b/blog_project/blog/blog.db differ
diff --git a/blog_project/blog/forms.py b/blog_project/blog/forms.py
index 76ff115..a6e91eb 100644
--- a/blog_project/blog/forms.py
+++ b/blog_project/blog/forms.py
@@ -39,15 +39,17 @@ class LoginForm(FlaskForm):
 
 
 class UpdateProfileForm(FlaskForm):
-    username = StringField('user name', validators=[DataRequired(), Length(min=4, max=25)])    
+    username = StringField('user name', validators=[
+                           DataRequired(), Length(min=4, max=25)])
     password = PasswordField('password', validators=[DataRequired()])
 
 
 class PostForm(FlaskForm):
     title = StringField('title', validators=[DataRequired()])
     content = TextAreaField('content', validators=[DataRequired()])
+    tags = StringField('tags', validators=[DataRequired()])
+
 
 class SearchForm(FlaskForm):
     query = StringField('Post Title', validators=[DataRequired()])
-    submit = SubmitField('Search')    
-    
\ No newline at end of file
+    submit = SubmitField('Search')
diff --git a/blog_project/blog/models.py b/blog_project/blog/models.py
index 35bb197..55f211b 100644
--- a/blog_project/blog/models.py
+++ b/blog_project/blog/models.py
@@ -8,6 +8,13 @@ def load_user(user_id):
     return User.query.get(int(user_id))
 
 
+post_tags = db.Table('post_tags',
+                     db.Column('post_id', db.Integer,
+                               db.ForeignKey('post.id')),
+                     db.Column('tag_id', db.Integer, db.ForeignKey('tag.id'))
+                     )
+
+
 class User(db.Model, UserMixin):
     id = db.Column(db.Integer, primary_key=True)
     username = db.Column(db.String(30), unique=True, nullable=False)
@@ -25,6 +32,16 @@ class Post(db.Model):
     date = db.Column(db.DateTime, nullable=False, default=datetime.now)
     content = db.Column(db.Text, nullable=False)
     user_id = db.Column(db.Integer, db.ForeignKey('user.id'), nullable=False)
-    
+    tags = db.relationship('Tag', secondary=post_tags,
+                           backref=db.backref('posts', lazy='dynamic'))
+
+    def __repr__(self):
+        return f'{self.__class__.__name__}({self.id}, {self.title})'
+
+
+class Tag(db.Model):
+    id = db.Column(db.Integer, primary_key=True)
+    name = db.Column(db.String(30), unique=True, nullable=False)
+
     def __repr__(self):
-        return f'{self.__class__.__name__}({self.id}, {self.title})'
\ No newline at end of file
+        return f'{self.__class__.__name__}({self.id}, {self.name})'
diff --git a/blog_project/blog/routes.py b/blog_project/blog/routes.py
index 4a5c43c..64cdef5 100644
--- a/blog_project/blog/routes.py
+++ b/blog_project/blog/routes.py
@@ -1,7 +1,7 @@
 from flask import render_template, redirect, url_for, flash, request, abort
 from . import app, db, bcrypt
-from .forms import RegistrationForm, LoginForm, UpdateProfileForm, PostForm , SearchForm
-from .models import User, Post
+from .forms import RegistrationForm, LoginForm, UpdateProfileForm, PostForm, SearchForm
+from .models import User, Post, Tag
 from flask_login import login_user, current_user, logout_user, login_required
 
 
@@ -78,6 +78,7 @@ def profile():
 
     return render_template('profile.html', form=form)
 
+
 @app.route('/post/new', methods=['GET', 'POST'])
 @login_required
 def new_post():
@@ -88,6 +89,12 @@ def new_post():
             content=form.title.data,
             author=current_user
         )
+        tags_list = [tag.strip() for tag in form.tags.data.split(',')]
+        for tag_name in tags_list:
+            tag = Tag.query.filter_by(name=tag_name).first()
+            if not tag:
+                tag = Tag(name=tag_name)
+            post.tags.append(tag)
         db.session.add(post)
         db.session.commit()
         flash('post created')
@@ -111,31 +118,48 @@ def delete(post_id):
 @login_required
 def update(post_id):
     post = Post.query.get_or_404(post_id)
-    
+
     if post.author != current_user:
         abort(403)
 
     form = PostForm()
-    
+
     if form.validate_on_submit():
         post.title = form.title.data
         post.content = form.content.data
+        post.tags.clear()
+
+        tags_list = [tag.strip() for tag in form.tags.data.split(',')]
+        for tag_name in tags_list:
+            tag = Tag.query.filter_by(name=tag_name).first()
+            if not tag:
+                tag = Tag(name=tag_name)
+            post.tags.append(tag)
         db.session.commit()
         flash('post updated', 'success')
         return redirect(url_for('detail', post_id=post.id))
     elif request.method == 'GET':
         form.title.data = post.title
         form.content.data = post.content
+        form.tags.data = ','.join([tag.name for tag in post.tags])
         return render_template('update.html', form=form)
 
-@app.route('/post/search' , methods=['GET', 'POST'])
+
+@app.route('/post/search', methods=['GET', 'POST'])
 def search():
-    form = SearchForm()  
+    form = SearchForm()
     if form.validate_on_submit():
-        posts = Post.query.filter(Post.title.like(f"%{form.query.data}%")).all()
+        posts = Post.query.filter(
+            Post.title.like(f"%{form.query.data}%")).all()
         if posts:
-            return render_template('search.html', posts=posts , form=form)
+            return render_template('search.html', posts=posts, form=form)
         else:
-            flash('No such post has been found!','danger')
-            return render_template('search.html',form=form)    
-    return render_template('search.html', form=form)          
\ No newline at end of file
+            flash('No such post has been found!', 'danger')
+            return render_template('search.html', form=form)
+    return render_template('search.html', form=form)
+
+
+@app.route('/tag/<string:tag_name>')
+def tag_posts(tag_name):
+    tag = Tag.query.filter_by(name=tag_name).first_or_404()
+    return render_template('tag_posts.html', posts=tag.posts, tag_name=tag_name)
diff --git a/blog_project/blog/templates/detail.html b/blog_project/blog/templates/detail.html
index 9e7fa45..ce47d19 100644
--- a/blog_project/blog/templates/detail.html
+++ b/blog_project/blog/templates/detail.html
@@ -1,9 +1,15 @@
 {% extends 'base.html' %}
 
 {% block content %}
-    <h3>{{ post.title }}</h3>
-    <small>{{ post.author.username }}</small>
-    <small>{{ post.date.strftime('%Y-%m-%d') }}</small>
-    <hr>
-    <p>{{ post.content|safe }}</p>
+<h3>{{ post.title }}</h3>
+<small>{{ post.author.username }}</small>
+<small>{{ post.date.strftime('%Y-%m-%d') }}</small>
+<div>
+    {% for tag in post.tags %}
+    <a href="{{ url_for('tag_posts', tag_name=tag.name) }}"><span class="badge badge-secondary">{{ tag.name
+            }}</span></a>
+    {% endfor %}
+</div>
+<hr>
+<p>{{ post.content|safe }}</p>
 {% endblock content %}
\ No newline at end of file
diff --git a/blog_project/blog/templates/home.html b/blog_project/blog/templates/home.html
index c1997ce..6b7a873 100644
--- a/blog_project/blog/templates/home.html
+++ b/blog_project/blog/templates/home.html
@@ -1,18 +1,24 @@
 {% extends 'base.html' %}
 
 {% block content %}
-    <h3>Home Page {{ current_user.username }}</h3>
+<h3>Home Page {{ current_user.username }}</h3>
 
-    <div class="card">
-        {% for post in posts %}
-            <div class="card-body">
-                <h6>{{ post.title }}</h6>
-                <a href="{{ url_for('detail', post_id=post.id) }}" class="btn btn-info">Show</a>
-                {% if post.author == current_user %}
-                    <a href="{{ url_for('delete', post_id=post.id) }}" class="btn btn-danger">Delete</a>
-                    <a href="{{ url_for('update', post_id=post.id) }}" class="btn btn-primary">Update</a>                                
-                {% endif %}                
-            </div>
-        {% endfor %}
+<div class="card">
+    {% for post in posts %}
+    <div class="card-body">
+        <h6>{{ post.title }}</h6>
+        <div>
+            {% for tag in post.tags %}
+            <a href="{{ url_for('tag_posts', tag_name=tag.name) }}"><span class="badge badge-secondary">{{ tag.name
+                    }}</span></a>
+            {% endfor %}
+        </div>
+        <a href="{{ url_for('detail', post_id=post.id) }}" class="btn btn-info">Show</a>
+        {% if post.author == current_user %}
+        <a href="{{ url_for('delete', post_id=post.id) }}" class="btn btn-danger">Delete</a>
+        <a href="{{ url_for('update', post_id=post.id) }}" class="btn btn-primary">Update</a>
+        {% endif %}
     </div>
-{% endblock %}
+    {% endfor %}
+</div>
+{% endblock %}
\ No newline at end of file
diff --git a/blog_project/blog/templates/new_post.html b/blog_project/blog/templates/new_post.html
index 5cf5700..51afe3a 100644
--- a/blog_project/blog/templates/new_post.html
+++ b/blog_project/blog/templates/new_post.html
@@ -1,15 +1,18 @@
 {% extends 'base.html' %}
 
 {% block content %}
-    <form method="post">
-        {{ form.csrf_token }}
+<form method="post">
+    {{ form.csrf_token }}
 
-        {{ form.title.label}}
-        {{ form.title}}
+    {{ form.title.label}}
+    {{ form.title}}
 
-        {{ form.content.label }}
-        {{ form.content }}
+    {{ form.content.label }}
+    {{ form.content }}
 
-        <input type="submit" value="Save">
-    </form>
+    {{form.tags.label}}
+    {{form.tags}}
+
+    <input type="submit" value="Save">
+</form>
 {% endblock content %}
\ No newline at end of file
diff --git a/blog_project/blog/templates/tag_posts.html b/blog_project/blog/templates/tag_posts.html
new file mode 100644
index 0000000..6e7a6c9
--- /dev/null
+++ b/blog_project/blog/templates/tag_posts.html
@@ -0,0 +1,18 @@
+{% extends 'base.html' %}
+
+{% block content %}
+<h3>Posts tagged with "{{ tag_name }}"</h3>
+
+<div class="card">
+    {% for post in posts %}
+    <div class="card-body">
+        <h6>{{ post.title }}</h6>
+        <a href="{{ url_for('detail', post_id=post.id) }}" class="btn btn-info">Show</a>
+        {% if post.author == current_user %}
+        <a href="{{ url_for('delete', post_id=post.id) }}" class="btn btn-danger">Delete</a>
+        <a href="{{ url_for('update', post_id=post.id) }}" class="btn btn-primary">Update</a>
+        {% endif %}
+    </div>
+    {% endfor %}
+</div>
+{% endblock %}
\ No newline at end of file
diff --git a/blog_project/blog/templates/update.html b/blog_project/blog/templates/update.html
index 5cf5700..51afe3a 100644
--- a/blog_project/blog/templates/update.html
+++ b/blog_project/blog/templates/update.html
@@ -1,15 +1,18 @@
 {% extends 'base.html' %}
 
 {% block content %}
-    <form method="post">
-        {{ form.csrf_token }}
+<form method="post">
+    {{ form.csrf_token }}
 
-        {{ form.title.label}}
-        {{ form.title}}
+    {{ form.title.label}}
+    {{ form.title}}
 
-        {{ form.content.label }}
-        {{ form.content }}
+    {{ form.content.label }}
+    {{ form.content }}
 
-        <input type="submit" value="Save">
-    </form>
+    {{form.tags.label}}
+    {{form.tags}}
+
+    <input type="submit" value="Save">
+</form>
 {% endblock content %}
\ No newline at end of file