To use mongodb with php you need to use mongodb php driver. Download the driver from the url Download PHP Driver. Make sure to download latest release of it. Now unzip the archive and put php_mongo.dll in your PHP extension directory ("ext" by default) and add the following line to your php.ini file:

extension=php_mongo.dll

Make a connection and Select a database

To make a connection, you need to specify database name, if database doesn't exist then mongodb creates it automatically.
Code snippets to connect to database would be as follows:

<?php
   // connect to mongodb
   $m = new MongoClient();
   echo "Connection to database successfully";
   // select a database
   $db = $m->mydb;
   echo "Database mydb selected";
?>

When program is executed, it will produce the following result:

Connection to database successfully
Database mydb selected

Create a collection

Code snippets to create a collection would be as follows:

<?php
   // connect to mongodb
   $m = new MongoClient();
   echo "Connection to database successfully";
   // select a database
   $db = $m->mydb;
   echo "Database mydb selected";
   $collection = $db->createCollection("mycol");
   echo "Collection created succsessfully";
?>

When program is executed, it will produce the following result:

Connection to database successfully
Database mydb selected
Collection created succsessfully

Insert a document

To insert a document into mongodb, insert() method is used.
Code snippets to insert a documents:

<?php
   // connect to mongodb
   $m = new MongoClient();
   echo "Connection to database successfully";
   // select a database
   $db = $m->mydb;
   echo "Database mydb selected";
   $collection = $db->mycol;
   echo "Collection selected succsessfully";
   $document = array( 
      "title" => "MongoDB", 
      "description" => "database", 
      "likes" => 100,
      "url" => "http://www.tutorialspoint.com/mongodb/",
      "by", "tutorials point"
   );
   $collection->insert($document);
   echo "Document inserted successfully";
?>

When program is executed, it will produce the following result:

Connection to database successfully
Database mydb selected
Collection selected succsessfully
Document inserted successfully

Find all documents

To select all documents from the collection, find() method is used.
Code snippets to select all documents:

<?php
   // connect to mongodb
   $m = new MongoClient();
   echo "Connection to database successfully";
   // select a database
   $db = $m->mydb;
   echo "Database mydb selected";
   $collection = $db->mycol;
   echo "Collection selected succsessfully";

   $cursor = $collection->find();
   // iterate cursor to display title of documents
   foreach ($cursor as $document) {
      echo $document["title"] . "\n";
   }
?>

When program is executed, it will produce the following result:

Connection to database successfully
Database mydb selected
Collection selected succsessfully
{
   "title": "MongoDB"
}

Update a document

To update a document , you need to use update() method.
In the below given example we will update the title of inserted document to MongoDB Tutorial. Code snippets to update a document:

<?php
   // connect to mongodb
   $m = new MongoClient();
   echo "Connection to database successfully";
   // select a database
   $db = $m->mydb;
   echo "Database mydb selected";
   $collection = $db->mycol;
   echo "Collection selected succsessfully";

   // now update the document
   $collection->update(array("title"=>"MongoDB"), array('$set'=>array("title"=>"MongoDB Tutorial")));
   echo "Document updated successfully";
   // now display the updated document
   $cursor = $collection->find();
   // iterate cursor to display title of documents
   echo "Updated document";
   foreach ($cursor as $document) {
      echo $document["title"] . "\n";
   }
?>

When program is executed, it will produce the following result:

Connection to database successfully
Database mydb selected
Collection selected succsessfully
Document updated successfully
Updated document
{
   "title": "MongoDB Tutorial"
}

Delete a document

To delete a document , you need to use remove() method.
In the below given example we will remove the documents that has title MongoDB Tutorial. Code snippets to delete document:

<?php
   // connect to mongodb
   $m = new MongoClient();
   echo "Connection to database successfully";
   // select a database
   $db = $m->mydb;
   echo "Database mydb selected";
   $collection = $db->mycol;
   echo "Collection selected succsessfully";
   
   // now remove the document
   $collection->remove(array("title"=>"MongoDB Tutorial"),false);
   echo "Documents deleted successfully";
   
   // now display the available documents
   $cursor = $collection->find();
   // iterate cursor to display title of documents
   echo "Updated document";
   foreach ($cursor as $document) {
      echo $document["title"] . "\n";
   }
?>

When program is executed, it will produce the following result:

Connection to database successfully
Database mydb selected
Collection selected succsessfully
Documents deleted successfully

In the above given example second parameter is boolean type and used for justOne field of remove() method.
Remaining mongodb methods findOne(), save(), limit(), skip(), sort() etc works same as explained in above tutorial.