// First, reserve email capacity for the current Apex transaction to ensure
                       
// that we won't exceed our daily email limits when sending email after
                       
// the current transaction is committed.
Messaging.reserveSingleEmailCapacity(2);

// Processes and actions involved in the Apex transaction occur next,
// which conclude with sending a single email.

// Now create a new single email message object
// that will send out a single email to the addresses in the To, CC & BCC list.
Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();

// Strings to hold the email addresses to which you are sending the email.
String[] toAddresses = new String[] {'user@acme.com'};
String[] ccAddresses = new String[] {'smith@gmail.com'};
 

// Assign the addresses for the To and CC lists to the mail object.
mail.setToAddresses(toAddresses);
mail.setCcAddresses(ccAddresses);

// Specify the address used when the recipients reply to the email.
mail.setReplyTo('support@acme.com');

// Specify the name used as the display name.
mail.setSenderDisplayName('Salesforce Support');

// Specify the subject line for your email address.
mail.setSubject('New Case Created : ' + case.Id);

// Set to True if you want to BCC yourself on the email.
mail.setBccSender(false);

// Optionally append the salesforce.com email signature to the email.
// The email address of the user executing the Apex Code will be used.
mail.setUseSignature(false);

// Specify the text content of the email.
mail.setPlainTextBody('Your Case: ' + case.Id +' has been created.');

mail.setHtmlBody('Your case:<b> ' + case.Id +' </b>has been created.<p>'+
     'To view your case <a href=https://na1.salesforce.com/'+case.Id+'>click here.</a>');

// Send the email you have created.
Messaging.sendEmail(new Messaging.SingleEmailMessage[] { mail });