If you are planning to hide show some span based on click event which is initially hidden with style="display:none" then .toggle() is best option to go with.
$("span").toggle();
Reasons : Each time you don't need to check whether the style is already there or not. .toggle() will take care of that automatically and hide/show span based on current state.
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<input type="button" value="Toggle" onclick="$('#hiddenSpan').toggle();"/>_x000D_
<br/>_x000D_
<br/>_x000D_
<span id="hiddenSpan" style="display:none">Just toggle me</span>
_x000D_