# Overview

All operations in ND4J and SameDiff are available in "Operation Namespaces". Each namespace is available on the `Nd4j` and `SameDiff` classes with its lowercase name. 

For example, if you want to use the [absoluteDifference](https://deeplearning4j.konduit.ai/en-1.0.0-beta7/loss#absolutedifference) operation it would look like this

```java
// ND4J mode
INDArray output = Nd4j.loss.absoluteDifference(labels, predictions, null);

// SameDiff mode
SDVariable output = SameDiff.loss.absoluteDifference(labels, predictions, null);
```

## Namespaces

{% content-ref url="bitwise" %}
[bitwise](https://deeplearning4j.konduit.ai/en-1.0.0-beta7/operation-namespaces/bitwise)
{% endcontent-ref %}

{% content-ref url="linalg" %}
[linalg](https://deeplearning4j.konduit.ai/en-1.0.0-beta7/operation-namespaces/linalg)
{% endcontent-ref %}

{% content-ref url="math" %}
[math](https://deeplearning4j.konduit.ai/en-1.0.0-beta7/operation-namespaces/math)
{% endcontent-ref %}

{% content-ref url="random" %}
[random](https://deeplearning4j.konduit.ai/en-1.0.0-beta7/operation-namespaces/random)
{% endcontent-ref %}

{% content-ref url="baseops" %}
[baseops](https://deeplearning4j.konduit.ai/en-1.0.0-beta7/operation-namespaces/baseops)
{% endcontent-ref %}

{% content-ref url="cnn" %}
[cnn](https://deeplearning4j.konduit.ai/en-1.0.0-beta7/operation-namespaces/cnn)
{% endcontent-ref %}

{% content-ref url="image" %}
[image](https://deeplearning4j.konduit.ai/en-1.0.0-beta7/operation-namespaces/image)
{% endcontent-ref %}

{% content-ref url="loss" %}
[loss](https://deeplearning4j.konduit.ai/en-1.0.0-beta7/operation-namespaces/loss)
{% endcontent-ref %}

{% content-ref url="nn" %}
[nn](https://deeplearning4j.konduit.ai/en-1.0.0-beta7/operation-namespaces/nn)
{% endcontent-ref %}

{% content-ref url="rnn" %}
[rnn](https://deeplearning4j.konduit.ai/en-1.0.0-beta7/operation-namespaces/rnn)
{% endcontent-ref %}