A hyphen is used in writing to join two words together or between the syllables of a word when it is divided at the end of a line of text. Hyphens must never be used interchangeably with dashes which are longer than a hyphen and there should be no spaces around hyphens.
The Hyphen
Hyphens' main purpose is to glue words together, to show that two or more elements in a sentence are linked.
Compound Words
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The Compound word should be hyphenated when they appear before a noun. Compound words should be hyphenated when two nouns come together to make a verb (i.e. to roller-skate). Made-up compound words used in creative writing should be hyphenated.
Example of a Compound Word
Some examples of compound words: Skateboard. Grasshopper. Baseball. Grandfather. Sunflower. These words are formed by two or more words that result in a new word with a new meaning, for example; 'base' is the origin of something, e.g., the base of a pizza, ball is something to play within a certain sport, e.g., golf, tennis, volleyball, snooker etc., base+ ball = baseball which is a ball game and forms a completely new word.
Hyphen can make a difference in meaning
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The Hyphen [-]: This is far less used in English than in Afrikaans. English compound words are often written as two or three words; e.g., All at once, a Gorgonzola cheese factory. No rules can be given about the use of the hyphen, except this: use a hyphen if there is any doubt about which words in a sentence belong together to form one compound word; e.g., "Black and white cats abound in that street" means something different from "Black-and-white cats abound in that street."
SOURCE: EBH Joubert; English Grammar & Punctuation Marks
https://www.grammarbook.com/punctuation/hyphens.asp
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