Concrete is a material composed of

• Cement- Most commonly Portland cement
• Fine Aggregates- Commonly sand
• Coarse Aggregates- Commonly crushed stone or gravel
• Potable Water- The water must be potable (drinkable, without salts or impurities)

and can also have admixtures which affect its properties.
Concrete does not dry, rather it undergoes a chemical reaction called hydration. Its consistency can be managed by varying the water/cement ratio, and the addition of some admixtures.