Laravel Relationship
One To one [User -> Address, Phone]
id Step Code
1 Table 1 
User
id, name, email
2 Table 2 
Address
id, user_id, address
3 Table 3 
Phone
id, user_id, mobile
4 Relation To 
User To [Address, phone]
5 Model 1 [User] 
User Model
public function getAddress(){
        return $this->hasOne('App\Address');
        return $this->hasOne(Address::class);
        return $this->hasOne(Address::class, 'foreign_key');
        return $this->hasOne(Address::class, 'user_id');
        return $this->hasOne(Address::class, 'foreign_key', 'local_key/Primary_key');
        return $this->hasOne(Address::class, 'user_id', 'id');
    }
    public function getPhone(){
        return $this->hasOne(Post::class);
    }
6 Controller 
use App\User;
use App\Post;

public function index(){

      $data['Users'] = User::all();
      $data['Users'] = User::with('getAddress', 'getPhone')->get();

      foreach ($data['Users'] as $User) {
         echo "Name: " .$User->name. "<br>";         
         echo "Address: " .$User->getAddress->address."<br>";         
         echo "Phone" .$User->getPhone->phone;
      }
}
7 Blade 
@php
   $users = App\User::all();
@endphp

@foreach($users as $user)
   {{ $user->name}}
   {{ $user->getAddress->address}}
   {{ $user->getPhone->Phone}}
@endforeach
One To one [Inverse] [Phone -> User]
id Step Code
1 Table 1 
User
id, name, email
2 Table 2 
Phone
id, user_id, phone
3 Relation To 
Phone To [User]
4 Model 2 [Phone] 
public function user(){
   return $this->belongsTo(User::class);
}

N:B: In this "belongsTo" function Name always will be model name.
Example: If model name "User", the function name will be "user or User".
But if use "getUser" , the function will be face problem.
So always function name will be as like "Model" name.
5 Controller 
use App\User;
use App\Phone;

public function index(){
   $phones = Phone::all();
   foreach ($phones as $phone) {
      echo "Phone: " .$phone->phone. "<br>";         
      echo "Name: " .$phone->user->name."<br>";
   }
}
6 Blade 
@php
   $phones = App\Phone::with('user')->get();
@endphp

@foreach($phones as $phone)
   {{ $phone->phone}}
   {{ $phone->user->name}}
   {{ $phone->user->email}}
@endforeach
One To Many [Post ->Comments]
id Step Code
1 Table 1 
Post
id, post
2 Table 2 
Comment
id, post_id, comment
3 Relation To 
Post To [Comment]
4 Model 1 [Post] 
public function comments(){
   return $this->hasMany(Comment::class);
}
5 Controller 
use App\Post;
use App\Comment;

public function index(){

   $posts = Post::all();

   foreach ($posts as $post) {
      foreach ($post->comments as $comment) {
         echo $comment->comment;
      }
   }
}
6 Blade 
@foreach($posts as $post)
   <tr class="text-center">
      @php
         $rowspan =$post->comments->count();
         $totalRow = $rowspan+1;
      @endphp

      <td rowspan="{{$totalRow}}">{{ $post->id}}</td>
      <td rowspan="{{$totalRow}}">{{ $post->post}}</td>
      @foreach($post->comments as $comment)
         <tr>
            <td>{{ $comment->comment}}</td>                                       
         </tr>
      @endforeach
   </tr>
 @endforeach
7 Table 1 
Post
id, post
8 Table 2 
Comment
id, post_id, comment
9 Relation To 
Post To [Comment]
10 Model 1 [Post] 
public function comments(){
   return $this->hasMany(Comment::class);
}
11 Controller 
use App\Post;
use App\Comment;

public function index(){

   $posts = Post::all();

   foreach ($posts as $post) {
      foreach ($post->comments as $comment) {
         echo $comment->comment;
      }
   }
}
12 Blade 
@foreach($posts as $post)
   <tr class="text-center">
      @php
         $rowspan =$post->comments->count();
         $totalRow = $rowspan+1;
      @endphp

      <td rowspan="{{$totalRow}}">{{ $post->id}}</td>
      <td rowspan="{{$totalRow}}">{{ $post->post}}</td>
      @foreach($post->comments as $comment)
         <tr>
            <td>{{ $comment->comment}}</td>                                       
         </tr>
      @endforeach
   </tr>
 @endforeach
One To Many [Inverse] [Post ->User, Category]
id Step Code
1 Table 1 
User
id, name
2 Table 2 
Category
id, categoryName
3 Table 3 
Post
id, user_id, category_id, post, description
4 Relation To 
Post To [User, Category]
5 Model 3 [Post] 
public function user(){
   return $this->belongsTo(User::class);
} 

public function category(){
   return $this->belongsTo(Category::class);
}
6 Controller 
use App\User;
use App\Category;
use App\Post;

public function index(){

   $posts = Post::all();

   foreach ($posts as $post) {
      echo $post->id;
      echo $post->user->name;
      echo $post->category->categoryName;
      echo $post->post;
      echo $post->description;   
   }
}
7 Blade 
@php
   $posts = App\Post::all();
@endphp
@foreach($posts as $post)
   <tr class="text-center">
      <td>{{ $post->id}}</td>
      <td>{{ $post->user->name}}</td>
      <td>{{ $post->category->categoryName}}</td>
      <td>{{ $post->title}}</td>
      <td>{{ $post->description}}</td>
   </tr>
 @endforeach
Many To Many [User ->Category [Via Post]]
id Step Code
1 Table 1 
User
id, name
2 Table 2 
Category
id, categoryName
3 Table 3 
Post
id, user_id, category_id
4 Relation To 
User to [Category]
5 Model 1 [User] 
public function category(){
   return $this->belongsToMany('App\Category', 'App\Post');
   // return $this->belongsToMany(Category::class, Post::class);
   // return $this->belongsToMany('App\Category', 'App\Post', 'user_id', 'category_id');
}
6 Controller 
use App\User;
use App\Category;
use App\Post;

$users = App\User::all();

foreach($users as $user){
   echo $user->name;
   foreach($user->category as $categoryName)
      echo $categoryName->categoryName;
   }
}
7 Blade 
@php
   $users = App\User::all();
@endphp
@foreach($users as $user)
   <tr class="text-center">
      @php
         $rowspan =$user->category->count();
         $totalRow = $rowspan+1;
      @endphp

      <td rowspan="{{$totalRow}}">{{ $user->id}}</td>
      <td rowspan="{{$totalRow}}">{{ $user->name}}</td>
      @foreach($user->category as $categoryName)
         <tr>
            <td>{{ $categoryName->categoryName }}</td>
         </tr>      
      @endforeach     
   </tr>
@endforeach