I have seen people compromising on the quality of the camera bag or not buying proper bag according to shooting style. A good quality and a proper camera bag not only protects your expensive gear, but also allows you to move around with your equipments for a longer duration without any fatigue. You need to evaluate your shooting style and select a camera bag. Let’s see some of the camera bag types and its use.
Camera Holsters: A Camera Holsters is a small camera bag, which can carry your camera with one lens attached to it. You can also carry additional accessories like lens cleaning kit, remotes, few filters. These bags are very handy and can be carried inside your travel bag. Perfect bag if you want to carry only one body with lens. 
Waist Belt: Waste belt is very useful for quick access to your camera. Many waist belts come with modular compartment for keeping extra lens, flash etc. These bags are perfect for those who want to travel light with just few extra lenses.
Shoulder Bag: These bags are also known as messenger bag. These are one of the most popular type of camera bag. Many professional likes to carry this type of camera bag. These bags come with different size and capacity. Although it provides a easy access to all your equipment, carrying a shoulder bag for a long time might hurt your shoulder particularly with all your professional equipment. Perfect for a short walk with your equipment but not recommended for all day long shoot with the bag on your shoulder.
Backpacks: Comfortable for all day long use. It comes with different sizes and can carry loads of equipment. A quality backpack with a waist belt and chest belt gives you extra comfort so that you can focus completely on photography. These bags also allow you to move freely around your shooting location or even give you liberty to run without damaging your expensive equipment. There are many manufactures who make backpack for hikers with a removable camera compartments.
Rolling Cases: These are also known as trolley cases. Ultimate solution for carrying hell lot of equipment with extra complete protection from being dropped, kicked or run over. However these are good when you have assistants to carry your equipment and you are moving in a vehicle. Not suitable for travel photography.
A camera bag not only protects your gears, but also gives you comfort to carry with them. A well though decision will help you to shoot for a longer duration.
