There are many times you will need to communicate, but it's just not possible or frowned upon. It may be inappropriate to speak aloud, impossible by distance, imprudent to speak, dangerous, or impossible.
[link to www.freewebs.com
I love to read. I always have. As an adolescent, I would often go to library, check out ten or more books, devour them, and return in a few days. Don't read good books, there isn't time. Read great ones.
While there one day, some librarian had hung up a fingerspelling chart for American Sign Language(ASL) . I'd read a book on codes using morse or writing with lemon juice or using symbol like hierogylphics or kanji, and I fascinated by non-verbal means of communication. I stuck around until I could replicate all of them, went and got my sister, and we both learned it in about an hour. Then we used it to talk sometimes for fun on long drives in the car, or simply as a game.
Because I'd practiced fingerspelling at age eleven, it unexpectedly prepared me for my first real summer camp at age 14. One of the young ladies named T_____ was deaf, and gorgeous. Only two other people could speak her language. Since I could speak in the “baby language of fingerspelling”, I could communicate albeit painfully slow. She was incredibly sweet, kind, and considerate, and drop dead gorgeous. Those are rare qualities, and were high motivators for me to learn more.
We wrote each other. I encouraged her to come back to camp. I purchased a book on ASL in the meantime, and learned the entire book by practicing and holding up signs in the mirror. My sister was minimally interested, so she learned some, and decided to come to camp too. T decided to come to camp again, and brought another of her deaf friends. Her brother translated everything for them, but still few people at first could communicate. They did see we had minimal trouble, so a few there asked out of curiosity, and we taught them. By the end of the camp week, almost everyone (more than forty kids and adults) could fingerspell, and some could speak in rudimentary sign words.
A few years later when I was a young man, I had a beautiful girlfriend, and I'd sit next to her in church, and we were so absorbed in each other, that while we were supposed to be listening to the sermon, we'd make fingerspelling signs with our hands surreptitiously. It made us closer.
Several charts are at the website above, one of which is fingerspelling. It is painfully slow. The easiest thing to do is practice each of the individual fingerspelling hand positions, then do them randomly with the other person guessing them, then spell small words, and so on. In many cases people will guess the word as you are spelling it, so you need not spell the whole word.
If you got a book on ASL, then you could silently communicate with the people in your group, and depending on the hand movements, communicate over a distance. The military uses this process:
[link to www.specialoperations.com
A universal sign of distress is an upside down flag. A white flag hung up is a universal sign for distress too. A black flag hung up is a universal sign of disease present. Such things could be used in a pandemic to alert medical personnel.
All energy vibrates at certain oscillations. Some of it is visible, and we see this as white light and color. Other is invisible to our eyes as the rods and cones that make up the color and black/white optical receivers cannot see those frequencies. Other frequencies can be picked up by specially constructed electronics called receivers. Other devices can transmit those frequencies and receive them too. This allows AM, FM, shortwave, VHF, UHF, and other frequencies to transmit over great distances.
People do not realize this, but communication often occurs on narrow bands of the spectrum and on not many frequency choices. The early wireless telephones were like this, and anyone with a special radio scanner could listen in on conversations. Even cell phone communications could be picked up this way. Journalists listened in on many celebrity communications, and picked up information, which they then published.
Even to this day, many frequencies on baby monitors, wireless video cameras, some cordless telephones and cell phones can be easily picked up depending upon the technical expertise of electronics enthusiasts. In a SHTF scenario, you should take this to heart. Any communication might be intercepted.
Here's a comprehensive list of frequencies that are used and in what capacity:
[link to www.radioreference.com
If you know the ones that are most likely to help you in a bug in or bug out situation, then you'll save time gathering information.
Local radio/HAM enthusiasts will often meet in your area. In the event of a pandemic or a SHTF scenario, they might be the best means of transmitting information across distances, and allowing the flow of information. It could then be relayed to progressive further distances. They usually publish the frequencies that are used locally by emergency responders. Such folks have special codes to describe situations. This gives some privacy as it takes a little time to know what that code means. If you knew the code, and things were degenerating, then you would be alerted before the rest of the people.
[link to www.radiolabs.com
Because things could break down, the medium of the Internet, radio, or television could break down, even if power was still operating. Prior to the Internet, there were ways of communicating like the Internet, they were just simpler means to transmit that information. Such ways might be used to communicate to people, but would be extremely slow compared to the normal Internet since they'd be relayed.
One such alternative is packet radio: [link to www.tapr.org
Another weblink which descibes alternatives: [link to en.wikipedia.org