I am writing some code in Ruby on Rails to **Create an object**.

I am using **Ruby 2.0** and **Rails 4.0.3** in my Application.

I have a Model called:

```
class GroupUsers < ActiveRecord::Base
  belongs_to :users
  belongs_to :group

```

This is basically a ManyToMany mapping between Users and Groups.
So, today I was creating an object for this Model.

But I found out I could follow **two syntax** for this, as follows

```
GroupUsers.create( :user => user, :group => group )

```

Or

```
GroupUsers.create( user: user, group: group )

```

Basically since this is **related to creating a Hash** so it must be a question of **the best practice in Ruby**. 

**Which syntax should be preferred ?**