'Concealed carry' means that you are allowed to carry a firearm on your person, concealed from view. The typical example of this would be a pistol in a holster,

'Concealed carry' means that you are allowed to carry a firearm on your person, concealed from view. The typical example of this would be a pistol in a holster, in your waistband, inside of your shirt or jacket. California doesn't allow 'open carry', which many other states do. This allows you to carry a pistol in a holster outside of your jacket/shirt so that it can be seen.