Sender:

The sender's email address or the name of the sender.

Recipients:

The recipients of the message.

CC:

Only the CC recipients of the message.

BCC:

Only the BCC recipients of the message. Obviously this can only be applied to outgoing filters.

Sender or Recipients:

The sender's email address or the name of the sender or the recipients of the message.

Subject:

The subject line of the message.

Specific Header:

Any header including custom ones.

If a message uses a header more than once, Evolution pays attention only to the first instance, even if the message defines the header differently the second time. For example, if a message declares the Resent-From: header as "engineering@example.com" and then restates it as "marketing@example.com", Evolution filters as though the second declaration did not occur. To filter on messages that use headers multiple times, use a regular expression.

Message Body:

Searches in the actual text of the message.

Expression:

(For programmers only) Match a message according to an expression you write in the Scheme language used to define filters in Evolution.

Date sent:

Filters messages according to the date on which they were sent. First, choose the conditions you want a message to meet, such as before a given time or after a given time. Then choose the time. The filter compares the message's time stamp to the system clock when the filter is run, or to a specific time and date you choose from a calendar. You can also have it look for a message within a range of time relative to the filter, such as two to four days ago.

Date received:

This works the same way as the Date Sent option, except that it compares the time you received the message with the dates you specify.

Label:

Messages can have labels of Important, Work, Personal, To Do, or Later. You can set labels with other filters or manually.

Score:

Sets the message score to any whole number greater than 0. You can have one filter set or change a message score, and then set up another filter to move the messages you have scored. A message score is not based on anything in particular: it is simply a number you can assign to messages so other filters can process them.

Size (kB):

Sorts based on the size of the message in kilobytes.

Status:

Filters according to the status of a message. The status can be Replied To, Draft, Important, Read, or Junk.

Follow Up:

Checks whether the message is flagged for follow-up.

Completed On:

Attachments:

Checks whether there is an attachment for the email.

Mailing List:

Filters based on the mailing list the message came from. This filter might miss messages from some list servers, because it checks for the X-BeenThere header, which is used to identify mailing lists or other redistributors of mail. Mail from list servers that do not set X-BeenThere properly are not be caught by these filters.

Regex Match:

(For programmers only) If you know your way around a regex, or regular expression, this option allows you to search for complex patterns of letters, so that you can find, for example, all words that start with a and end with m, and are between six and fifteen letters long, or all messages that declare a particular header twice. For information about how to use regular expressions, check the man page for the grep command.