What types of plaid are associated with Scottish families?

The types of plaids associated with Scottish families are called tartans, and they are woven of various numbers of vertical and horizontal stripes with dozens of different color choices. The specific tartans associated with hundreds of Scottish clans are found in "The Scottish Register of Tartans."

You can search for specific tartans on TartanRegister.gov by clan, designer, colors absent or present, and date registered, if known. Tartans.net contains an enormous amount of information on tartan types, making and wearing of tartans, reading and tracking of tartans, and Scottish heritage. Tartans.net also has a collection of links to order tartan-related items and materials.