The taxi vehicle is unique because it is only used by taxi companies and cannot be used for personal use.
When it comes to emergency vehicles, I came into this experience knowing that that flashing red, white and blue lights meant "emergency". In the U.K., all emergency vehicles and personnel are identified by neon colors. The ambulance and police cars are often neon yellow and green. The lights are neon orange. At night time, the vehicles really stick out.
I grew up in Washington D.C., so I'm also used to undercover police cars and police officers. The concept of undercover police cars and police officers is non-existent here. All police personal are required to wear neon vests over their uniforms. This allows them to stand out in an emergency.
The majority of people get around by walking, driving or taking the bus. Taxis are mostly used for getting to and from airports or bus stations and getting home late at night. Ambulances and police vehicles are used in the same ways as they are in the U.S.
For the most part, I get around by walking and riding buses. I've used Uber once with a group of friends and it was exactly like the U.S. I used a taxi once when my friends and I were traveling around Glasgow, Scotland. This part of Scotland did not have Uber/Lyft. Taxis were the only other mode of transportation besides cars/buses.
My taxi ride in Glasgow was the first time I've ever ridden in a taxi in my life. The process is fairly simple and a lot easier to navigate then Uber/Lyft. The taxis were already waiting at the bus station.