General Usage Rules In America, Canada, Australia and New Zealand, the general rule is that double quotes are used to denote direct speech. Single quotes are used to enclose a quote within a quote , a quote within a headline, or a title within a quote .
Single quotation marks are used to indicate quotations inside of other quotations .
echo “echo “$ SHELL “” echo /bin/bash. In other words, single quotes completely protect a string from the shell while double quotes protect some things (spaces for example) but allow variables and special characters to be expanded/interpreted correctly.
Quotation marks are also called inverted commas, speech marks, or quotes . Quotation marks can be used in two styles; single (‘ ‘ or ‘) or double (“ ” or “), and can also appear in two different typefaces; either as so called dumb or straight quotes (‘ or “) or as smart quotes (‘ ‘ or “ ”).
As a general rule, British usage has in the past usually preferred single quotes for ordinary use , but double quotes are now increasingly common; American usage has always preferred double quotes .
Use single quotes Use single – quotes for string literals, e.g. ‘my-identifier’, but use double – quotes for strings that are likely to contain single – quote characters as part of the string itself (such as error messages, or any strings containing natural language), e.g. “You’ve got an error!”.
Quotation marks around single words can occasionally be used for emphasis , but only when quoting a word or term someone else used . If a word needs to be emphasized but is not being quoted, you should avoid putting the word in quotes and use italics instead.
HTML Entities for Quotation Marks, Code Table
|«||«||Left-Pointing Double Angle Quotation Mark|
|»||»||Right-Pointing Double Angle Quotation Mark|
If you use single quotation marks, then you should use double quotation marks for a quote within a quote. If you use double quotation marks, then you should use single quotation marks for a quote within a quote.
Rule: Use single quotation marks inside double quotation marks when you have a quotation within a quotation . Example: Bobbi told me, “Delia said, ‘This will never work. ‘ ”
The backtick does exactly what you say it does. You have set a variable to an integer. When you put that variable inside backticks , bash will try to execute it as a command. Since it is not a command, you get the error you saw.
If you want to write content of variable $foo in ‘ use the character to escape single quote . Single quote may not occur between single quotes , even when preceded by a backslash, but this works: echo $ ‘I’m a linux admin.
If you are an American, using quotation marks could hardly be simpler: Use double quotation marks at all times unless quoting something within a quotation, when you use single. It’s different in the greater Anglosphere, where they generally use singles in books and doubles in newspapers.
Types of quotes In-text quotes . An in-text quote is a short quote that fits into and completes a sentence you’ve written. Indirect quotes . An indirect quote is when you paraphrase ideas from a source. Direct quotes . A direct quote is when you take text directly from a source without changing anything.
In the American system, periods and commas always go inside quotation marks (i.e., single AND double). Thus, sentences 1, 2, and 3 should look like this: The suspect told the arresting officer, “I was nowhere near the crime.” “Walk to the corner,” she explained to the child, “and turn left.”