"BB cream stands for blemish balm, blemish base, beblesh balm (apparently because of a trademark in Korea on the word "blemish"), and in Western markets,beauty balm. It is a cosmetic item sold mainly in East and Southeast Asia, although larger beauty brands are increasingly introducing BB creams to Western markets." (Sourced here)
The way I see it is as a multipurpose face balm designed to cut down on the number of products needed by combining them into one. They usually are a light coverage and in my view are a lite version of foundation without feeling bare. I think this makes them perfect for summer when the skin really dose need a chance to breath. I searched through all of the drugstore versions and couldn't make my mind up on which would be best until a saw a video on Wildkatmakeup Youtube channel (here). I decided if I was going to get one then why not pick a company that's been doing it all along.
I picked out of the four available Dr.Jart+ Water Fuse BB Beauty Balm in Boots on offer for £12 instead of £18. It also is a 50 ml which I think is a decent amount compared with many others being around 30 ml. It is coloured but much more translucent when applied. It has a dewy finish which I did apply powder to after ward but this didn't go cakey. It has an SPF 25 so protects my skin in the sun while being hydrating and oil free as well. It evened out my skin tone giving a very natural appearance allowing me to use less concealer and other fix it products. I would definitely recommend this and the others in the range where it suits skin types as apposed to three skin shades.