1)
I use the classifications of packaging styles as defined by the Airfix Collectors Club, which are explained in detail in the highly recommended website Collecting Airfix Kits .
Three packaging styles are relevant here : Type 1, Type 2, and Type 3 .
Type 2 ( headers and boxes) is my favorite Airfix boxart.
Early Type 1 header card artwork is a crude line drawing, and the design is split into red [or blue as seen on the Fokker Dr1 above ?] and white halves. The Airfix logo is a scroll which also contains the words "Products in Plastic".
Later Type 1 header cards for the Series 2 kits were a more sophisticated style, but the artwork is still pretty simple.
Type 2 style header cards was introduced in about 1959/60. The card is again split vertically in two colours with another vertical coloured stripe between the two halves. The Airfix logo looses the words "Products in Plastic".
Type 3 header cards were introduced in the Autumn of 1963 and lasted into the 1970s.
The term "type 0" is generally applied to any box style before the standardisation on the distinctive type 2 below. There are no known "type 1" boxes, this style being reserved for the plastic bag kits only.
Type 2 boxart is easily identified by the vertical stripe.
Type 3 boxart was used 1963-1973.