Some say there's no such thing as "palate building"--beer is just beer--just drink--what so complicated about it?
Of course some would say yes--there's a period of "palate building" for every newbie--that your taste bud/senses need some time( few months to a year or even longer...) to get use to/get around the different "stimulation" generated by different beer styles.
And--many also believe that drinking craft should start with the lightest, and gradually to the stronger/strongest beer--because a stronger beer( in taste/type--not just abv)would in theory "over-power/destroy" your palate, hence can't fully appreciate a perceived "weaker"beer .
Well, some people would just do the opposite--starting with the stronger( or even the strongest beer)--and reverse the sequence--if that suits you---why not?
Many would say low abv beer or session beer is anything with 5% abv or lower( though some might think 6% +- is still fine) --the idea is simple---yummy beer that won't kick your ass after one pint or a bottle--one that you could probably go for 3-4 during a drink session if you really love it so much.
if you have tasted quite a few crazy big beers--sometimes all you want is just tasty beer that's still complex yet easy to drink.
This may sound like a term more often associated with wine/whiskey, especially with the image of a guy holding a glass, a basket in waiting and spitting out...
In the world of Craft Beer there's such thing called tasting session too--and NO--we do not spit out( unless if the beer has gone bad or super duper badly made)
This is in fact the best way to not drink in quantity but quality--a group of few geeks/friends--each bring out a bottle or two of their best kept secret bottle/s--best way to enjoy good beer.