echo将内容输出到控制台或Web浏览器.

echo outputs content to the console or the web browser.

示例:

echo "Hey, this is now showing up on your screen!";

return在函数或方法的末尾返回一个值.

return returns a value at the end of a function or method.

示例:

function my_function()
{
    return "Always returns this";
}

echo my_function(); // displays "Always returns this"