A regular pre-roll starts with flower
A standard pre-roll contains dried cannabis in rolling paper, usually with a paper or cardboard tip. The preparation is done for you, while the cannabis inside is the same broad category as flower sold in a jar.
The paper tip is generally a mouthpiece or structural support, not a health-protective cigarette filter. Smoking cannabis still exposes your lungs to harmful smoke.
Whole flower, milled flower, and blends
Flower is generally ground or milled before rolling. A producer describing a pre-roll as whole flower usually means the starting material was buds; the flower inside the paper has still been broken up. A blend may combine more than one cultivar.
The starting material and grind can affect aroma, draw, and how evenly a pre-roll burns. Because you cannot inspect it like a jar of buds, the producer's description and your experience with that product are useful alongside the label.
“Milled” on its own does not mean an extract has been added. That is the distinction behind the word infused.
Infused means an extract has been added
An infused pre-roll combines dried cannabis with a concentrated product such as hash, kief, distillate, or another cannabis extract. The extract may be mixed into the material or included in another part of the product. Brand names can be inventive; the important part is what was added.
In Canada, infused pre-rolls containing a cannabis extract are classified as cannabis extracts, not simply dried cannabis. Their Total THC may be much higher than that of an ordinary pre-roll.
If you are a new or occasional consumer, Health Canada advises avoiding high-THC extracts because they increase the risk of strong impairment and adverse effects. The added concentrate changes the product, even when its size looks familiar.
Decode the names on the menu
Mini and king-size usually describe size. Diamond-infused generally points to added crystalline concentrate. A hash-hole commonly has a core of concentrate running through the flower. These names help describe the construction; the ingredients and package weight fill in the details.
For potency, look for Total THC and Total CBD. For flower or extract labels expressed in mg/g, dividing by ten gives an approximate percentage. For example, 250 mg/g is about 25% by weight. That is a concentration, not a prediction of exactly how much THC a person will inhale.
Further reading