In reference to your first question: Yes, the salt and pepper should always be passed together, even if only one is requested. The pepper shaker is on the left and the salt on the right.
Since more people use salt than pepper (and most people are right-handed), the salt shaker is placed to the right of the pepper shaker, in a position closer to the right hand.
Passing dishes or food:
If another guest asks for the salt or pepper, pass both together, even if a table mate asks for only one of them. Set any passed item, whether it's the salt and pepper shakers, a bread basket, or a butter plate, directly on the table instead of passing hand-to-hand.
The number of holes in salt and pepper shakers varies by culture, health and taste. Here in the US excessive salt is considered bad for you, so the salt shaker is the one with the fewer holes, but in parts of Europe it's the other way around.
The number of holes varies by culture, health, and taste. In the United States where excessive salt is considered unhealthy, salt is stored in the shaker with the fewer holes, but in parts of Europe where pepper was historically a rare spice, this is reversed.
In European countries, the scenario was the opposite with pepper because pepper, in its original form took forever to get a good amount from a shaker with just one hole. An old saying to determine which went where was: three holes for PePPer because of the three "p's".
Fortunately, you can reverse this disastrously bad turn of fortune by simply throwing salt over your shoulder. Your left shoulder. The origins of these two superstitions? The bad luck of spilling salt is supposedly from da Vinci's 'The Last Supper', in which Judas Iscariot knocks over a salt cellar.
It's important to note that the superstition calls for the offender to throw salt over the left (or "sinistra" - sinister) shoulder ie the devil's side with your right hand (your "good" side). In biblical times, salt was an expensive commodity.
Egypt and Portugal – Don't ask for salt and pepper
It's easy to instinctively reach for salt and pepper. Especially for Westerners. But in both Egypt and Portugal's food cultures, it is considered poor food etiquette because it tells the chef their food isn't seasoned well enough.
The short answer is that it varies by culture and also current health trends. Those wishing to limit their sodium intake (aka, those in the United States) use the top with the fewest holes in it for the salt. Practically speaking though, the real answer is to use whichever top gives you the result you want.
The most common contemporary belief requires you to toss a pinch of the spilt salt over your left shoulder, into the face of the Devil who lurks there.
Salt is usually placed to the right of the pepper because most people are right-handed, and salt is requested more than pepper (even though I prefer pepper).
Keep it in any corner from where it is not visible. It will absorb all the negative energy from the bathroom. If your bathroom has Vastu defects then it will help you to mitigate the negative results by using salt.
Salt should be stored in an airtight container in a cool, dry, dark location.
In ancient times salt was a valuable commodity primarily because it was hard to procure, making it very costly. A superstition says spilling salt will bring you bad fortune. As legend has it, you should take a pinch of the spilled salt and throw it over your left shoulder to cancel the bad luck.
Salt: Spilling salt is considered unlucky.
The only way out to turn back the bad luck is to throw some salt with your right hand over your left shoulder. It is also considered to be bad luck if you pass salt to another person.
Many cultures around the world have drawn upon the healing powers of salt to bless a space and draw out any negative forces. Japanese sumo wrestlers don't start their match until salt has been tossed into the ring to remove bad spirits, and Catholic priests have used salt during exorcisms (via Catholic Sacramentals).
The widespread superstition that spilling salt brings bad luck is believed to have originated with the overturned salt cellar in front of Judas Iscariot at the Last Supper, an incident immortalized in Leonardo Da Vinci's famous painting.
This signified Judas' betrayal of Jesus. The superstition states that if you throw salt over your shoulder, the bad luck is then reversed as you are throwing it behind you and focusing on the good to come. 2.
Salt falling means that Shukra and Chandra Navgrahas will bring troubles in a person's life in the near future. In life, there will be terrible luck. There will be strain and stress in the mind.
The other thing most of us do is put the salt in the shaker with the most amount of holes. The pepper goes in the shaker with the fewer amount of holes. That is the "rule".
Salt manufacturers said to put the salt in the shaker with the larger holes, while pepper manufacturers said to put the pepper in the shaker with more holes. The pepper manufacturer also said that since pepper is sometimes larger or coarser, the larger or more holes would accommodate it better.
Since salt crystals are larger (and tend to clump in humid conditions), their holes should be bigger. (However, after having shaken the dickens out of many a pepper shaker to yield only a dusting of product, I think it makes sense to put pepper in the shaker with the largest holes, so it flows at an acceptable rate.)