Using the Marketing module, you can send an Email to an individual contact, or a selection of contacts, without creating a campaign.
On your Contacts table/grid, click the checkbox next to the name of the contact(s) you wish to mail, then click on the ‘More’ button. Select the option ‘Send Email’ and this will bring up a search box. Search for the email you wish to send then click the blue ‘Send Email’ button to complete the procedure. This will send the email immediately to the contact.