The difference between print and echo in php and the difference between "" and''

The difference between print and echo in php and the difference between "" and ''can be output in the echo function at the same time, while in the print function, only one string can be output at the same time. At the same time, the echo function does not need parentheses, so the echo function is more like a statement than a function. & Lt ;? Differences between print and echo in php and the difference between "" and ""

In the echo function, multiple strings can be output at the same time, while in the print function, only one string can be output at the same time. At the same time, the echo function does not need parentheses, so the echo function is more like a statement than a function. In print "a", "B"; this sentence is wrong. only the echo function can be written like this.
--- The processing of single and double quotation marks is different in PHP. The content in the double quotation mark string can be interpreted and replaced, while the content in the single quotation mark string is always considered as a common character. If $ value = "I am a value"; echo "$ value ";-----? The output is: I am the value echo '$ value ';-----? The output is: $ value
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