<p>I see <a href="https://github.com/dgkanatsios/CKAD-exercises/blob/master/d.configuration.md#create-and-display-a-configmap-from-a-file-giving-the-key-special" rel="nofollow noreferrer">here</a> a syntax like this:</p>

<pre><code>kubectl create cm configmap4 --from-file=special=config4.txt
</code></pre>

<p>I did not find a description of what repetition of = and the <strong>special</strong> means here. 
Kubernetes documentation <a href="https://kubernetes.io/docs/tasks/configure-pod-container/configure-pod-configmap/#create-configmaps-from-files" rel="nofollow noreferrer">here</a> only denotes one time usage of <strong>=</strong> after <strong>--from-file</strong> while creating configmaps in kubectl. </p>

Farshid
<p>It appears from generating the YAML that this middle key mean all the keys that are being loaded from the file to be nested inside the mentioned key (special keyword in the question example).</p>

<p>It appears like this:</p>

<pre><code>apiVersion: v1
data:
  special: |
    var3=val3
    var4=val4
kind: ConfigMap
metadata:
  creationTimestamp: "2019-06-01T08:20:15Z"
  name: configmap4
  namespace: default
  resourceVersion: "123320"
  selfLink: /api/v1/namespaces/default/configmaps/configmap4
  uid: 1582b155-8446-11e9-87b7-0800277f619d
</code></pre>
