A simple master pattern that is used to make more detailed patterns.
Blocks generally have no design features other than what is required for fitting. A Block is usually made from a thin cardboard, not paper, so that the patternmaker can trace around it to create patterns. The term Block is more commonly used in Australia and the UK, while the term Sloper is used in the United States.
The Basic Block or Sloper Set consists of seven pieces: Bodice Front, Bodice Back, Sleeve, Skirt Front, Skirt Back, Pants Front and Pants Back. See the images below an example of each of these.
Image 1: Bodice Blocks
An example of a Bodice Block set: Front and Back.
This Front Bodice has darts in the side seam and waist, but other Bodice Blocks may have the darts in the shoulder seam and waist, or a single dart in the waist.
Image 2: Sleeve Block
An Example of a Sleeve Block.
This is a Fitted Sleeve Block as it has a dart in the elbow. Other Sleeve Block options include the two-piece Sleeve Block, which has a seamline under the arm, and the basic Sleeve Block with no dart/curve at the elbow.
Image 3: Skirt Blocks
An example of a Skirt Block set: Front & Back.
This Skirt Block as two darts in the front and two darts in the back. Other Skirt Blocks may have one dart in the front and the back, or two in the back and one in the front.
Image 4: Pants Blocks
An example of a Pants Block set: Front and Back.
These Pants Blocks have two darts in the back and one in the front. Other Pants Blocks may have two darts in both the front and the back. The shape of the leg may also differ.
You can have many more Blocks such as Jeans, Torso, Extended Line Dress, Jacket, Overgarment, Shirt., etc. Some blocks are made from scratch (examples are the basic blocks: Bodice, Sleeve, Skirt), others are made from an existing Block.