There are many types of jackets, each having an ideal use. The type of jacket you need will depend on the weather and conditions you are going to be wearing it in, as well as your own personal body temperature regulation.
3-in-1 jackets consist of multiple layers in one jacket. They will have a zip or snap in jacket, often of fleece or down, that fits into an outer jacket. Together they create a very warm combination, where the outer jacket functions as the weather resistant layer and the inner jacket provides the insulation and warmth.
Casual jackets are mostly about style. They are designed for looking good while walking around town, can be lightweight or heavily insulated, and vary from hip to knee length.
Fleece jackets are among the most versatile. Ranging from mid the heavy weight, fleece jackets make great spring and fall jackets, as well as being ideal for layering under ski jackets in the winter.
Insulated jackets are the most common style of active winter jackets. The insulation part of the jacket comes in different weights and different materials, with each weight and material offering a different amount of warmth. Providing a blend of warmth and protection from the elements, insulated jackets are easiest way to stay warm in the cold.
Insulator jackets are designed to be all about warmth. They are typically designed to fit well under shell jackets for added warmth, but they are very popular as lightweight fall and spring jackets as well.
One Piece suits are jackets and pants combined into one suit, and are the best option for warmth and ease. All the comfort of your childhood onesie packed into complete protection from the elements.
Shell jackets are the most modern approach to technical winter clothing. Made with single or multi layer lightweight fabric, shell jackets are built to keep the elements out. While they may have a lining for comfort, all the warmth comes from the layers you choose to put underneath the shell. This allows you to tailor the warmth of your apparel to the conditions of the day.
Soft Shell jackets are similar to a shell jacket, but made of a softer more stretchy fabric. Soft shells are typically the most breathable jackets, making them ideal for the spring and fall, layering, and a good piece to transition to après ski activities as well.
Vests are simply that. Made from fleece, down, or soft shell fabric, vest are all about adding additional warmth through layering in the area that needs it most.