# Field Values

### Specify default values

You can set a default value for any parameter for the value to be passed automatically:

![](/files/-Mjgt67WLU7ccycs8wZR)

Now when the user sends an email, he or she will not have to manually enter the `from email` parameter.

### Extract values from components on the Page

Let's say you have the Customers table. Once the user is selected in the Customers table, his or her email value will be used as the `User email` parameter that to send a promotional email with a Marketing tool. The succession of events will be this:

{% content-ref url="/pages/NbUCqqJ3sSw4FFTjiHSU" %}
[Extract values from components on the Page](/user-guide/design-and-structure/column-values/extract-values-from-components-on-the-page.md)
{% endcontent-ref %}


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