Simply...What's a Lager?
Lager is the most common style of beer in the world. The bottom-fermented techniques used to brew it result in a crisp, refreshing beer, though it's a surprisingly diverse group.
The yeasts used to ferment the beer collect at the bottom of the fermentation tank. Ales are just the opposite and use yeasts that are top-fermenting. Lager yeasts can also tolerate much lower temperatures than yeasts used for ales. The temperatures are around 7 to 12 degrees Celsius. The more tolerant lagers can handle longer ageing times than ales. Called "lagering," these beers can be aged for months at much lower cellar temperatures.
Where did lager come from?
While cold storage of beer, "lagering", in caves for example, was a common practice throughout the medieval period, bottom-fermenting yeast seems to have emerged as a hybridization in the early fifteenth century responsible for creating the hybrid yeast used to make lager.
Based on the numbers of breweries, lager brewing became the main form of brewing in the Kingdom of Bohemia between 1860 and 1870.
he rise of lager was entwined with the development of refrigeration as refrigeration made it possible to brew lager year-round and efficient refrigeration also made it possible to brew lager in more places and keep it cold until serving. The first large-scale refrigerated lagering tanks were developed for Sedelmayr's Spatan Brewery in Munich by Von Linda in 1870.
"I drink Lager not beer"
Please... Never say this.