Linguistics scientists consider a language living if it's changing. A language only stops changing when it's no longer being used.
Thanks to our constant use of computers a lot of signs and symbols have completely changed their meaning.
For example, the @ sign used to mean "at" but now it means "about" or "approximately." Having changed from an indication of precision it now means almost the opposite.
The # sign used to mean "number." Now it's called a hashtag and, while it doesn't exactly symbolize a word, using it at the beginning of something on the internet could be considered to mean, "at." In other words it has sort of taken over the original meaning of @.
And nobody knows why it is called a hashtag, but the word, hash, meant an jumbled up mess, usually, but not always, of food and a tag usually shows where to find something.
The & sign hasn't changed its meaning, but many people don't know it was originally a written word from latin. The word, et, means "and" and over time the two letters, e and t, got squished together to form the symbol, &.
Nobody really knows where the dollar sign, $, came from. It used to have two vertical lines on the capitol S and one suggestion is that it originally symbolized the United States currency as a capitol U on top of the S.
The cent sign (which isn't on my keyboard) of a letter, c, with a vertical line through it was based on the Latin word for one hundred since a cent is one hundredth part of a dollar. Maybe the vertical line was to make it similar to the dollar sign since it's also about money.
Obviously the language of symbols is a living language.