Awesome work! We’ve covered a lot of material in this lesson, so let’s review:

• Strings are collections of text that the computer treats as a single piece of data.
• A string can be any length and contain any letters, numbers, symbols, or spaces surrounded by quotation marks.
• In order to include certain characters inside strings we have to use escape sequences.
• An operator is a character that performs a task in our code.
• We can use the concatenation operator (.) to combine two strings into one.
• Variables are a fundamental programming concept which allow us to easily reuse data in our code.
• We declare a variable using the dollar sign ($) followed by the variable name and then use the assignment operator (=) to give it a value.
• PHP has variable parsing which allows us to include variables directly in our strings.
• Once a variable has been assigned, we can change its value. This is called reassignment.
• We can create an alias for a variable, instead of just a copy, using the reference assignment operator (=&).
• Operations to the right of the assignment operator will be evaluated before assignment takes place.
• The concatenating assignment operator (.=) is a shorthand notation for reassigning a string variable to its current value appended with another string value.

If that was a lot to take in, don’t worry about memorizing everything right away. Remember that when you want to explore more about the language, the documentation is a great place to get comfortable exploring.