Displaying Help Text in Visualforce Page

<apex:page standardController="Campaign" showHeader="true">
    <apex:form>
        <apex:pageBlock>
            <apex:pageBlockSection title="Information">
                <apex:pageBlockSectionItem HelpText="{!$ObjectType.Campaign.fields.Category__c.inlineHelpText}">
                    <apex:inputField value="{!Campaign.Category__c}" label="{!$ObjectType.Campaign.fields.Category__c.label}" />
                </apex:pageBlockSectionItem>
            </apex:pageBlockSection>
        </apex:pageBlock>
    </apex:form>
</apex:page>