Boeing recently unveiled the suit that astronauts will be wearing when they ride their upcoming Starliner capsule to the International Space Station (ISS). Officially called the Starliner Ascent and Entry Suit, it also answers to "Starliner spacesuit". Aside from its bold "Boeing blue" color, the Starliner spacesuit has numerous features worth noting. It is quite different in several ways from any suit that astronauts have ever worn before. These differences reflect an emphasis on mobility and comfort, efforts to blend the suit with its host spacecraft, and the specific emergency scenarios that the suit is designed for.
The most important thing to understand about the Starliner spacesuit is its role an "ascent and entry" suit. As such, it is only designed to be worn during launch and landing of the spacecraft. You won't see astronauts spacewalking in this suit (at least not for long!). The primary function of an ascent and entry suit is to keep the occupant alive if there is a problem inside the crew compartment during launch or landing. The scenarios with the highest probability (though still relatively unlikely) are loss of cabin pressurization or an internal fire.
Before getting to the specifics of the Starliner spacesuit, let's discuss the attributes of ascent/entry suits in generic terms. Previous generations of these suits have been derived from the pressure garments worn by pilots of high-altitude reconnaissance aircraft like the U-2 and SR-71. In some cases, the differences were negligible. Whether worn in an airplane or a spacecraft, the job such a suit is to provide its occupant with a tolerable atmospheric pressure, even when the outside pressure conditions are lethal.