If the gun is to be carried loaded...as it should be; it will be in one of the following states:
1: chamber loaded, no safety ie your Glock, M&P etc.
2: chamber loaded, hammer down safety on or off this would be for your beretta etc. They can be decocked and safety placed into the firing position. There are plenty of DA/SA guns that have a decocker and no safety.
3: hammer cocked, safety on. This is for your single action autos like the 1911, Hi Power and some other variants which are cocked and locked capable like some HKs and CZs.