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Justin Okpara
Justin Okpara

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Data types in JavaScript and PHP

Data types are the ways by which data can be declared in a programming language, different programming languages use different data types, although some of them can be similar.


JavaScript: JavaScript has 8 data types.

They are : Boolean, Array, object, number, undefined, null, string, Bigint

Boolean: Is usually a true of false declaration or statement

Array: Array is used to hold data types that are similar, can be declared by [], or the new array() function.

Object: This is one of the most widely used data types in JavaScript, it is the collection of data using key value pairs, using keys to access values of data, and values being the data that are being stored.

Undefined: Undefined can be defined as variables that weren't assigned any value, leaving them undefined until a data has been defined.
They are important in different programming languages for different reasons and are well used in imperative programming.

Null: Null can be defined as a variable that was intentionally defined to have no values.

String: This is the most widely used data type, encompasses a series of letters or alphabets.

Number: This data type is widely used for declaring variables which houses numbers or numerals as variables, they can come in as integers, double, or float.

Bigint: This type of data type is used to declare variable containing a very large set of numbers or integers.


PHP: PHP which is a widely used backend programming language has 8 data types.

They are: String, Array, object, resource, integers, float, Boolean and null.

Similarities and differences in data types between JavaScript and PHP


1 strings: The strings data type is similar in both languages, they're a series of letters or alphabets housed by a variable, the only difference between both of them is how they are being declared in each of the languages.

2 Boolean: Boolean in PHP or JavaScript are similar, they are used to represent truthy or falsy values.

3 Null: This data type is also very similar between both JavaScript and PHP, they are used to intentionally define variables with no values


1 Array: The array data type is different in both language, though they are the same in terms of the functionality but are different in terms of how they are being declared, the array data type is used to hold values that are similar.
To declare an array in JavaScript we use the [], or use the new array() method.
While to declare an array in PHP we only use the array() method, in as much as they have different syntax, both of them serve the same purpose which is to house data of similar kind.

2 Numbers vs integers and float: Each of this data type has a similar purpose which is to store anything that's numerical.
JavaScript uses the number data type, which is used to to store anything that is a numerical value, JavaScript does not group them in types but treats them all as one.
PHP is different in terms of how it treats numerical values, it uses the integer data type to store a numerical value that is a whole number, and uses the float data type do store numbers with exponential or decimals.

3 Objects: Objects are widely used in different programming languages and are used in both JavaScript and PHP.
JavaScript objects are used to store data with key value pairs and can be defined using the curly braces {}.
PHP on the other hand uses object but mainly as a version of the oop, which is the object oriented programming syntax, it creates a class with different methods and instances and uses the object function to initiate a class.

Both JavaScript and PHP have similar syntax in some aspects and still have their differences in their syntax, but they both can be used to solve the same type of issues.

Top comments (3)

wearypossum4770 profile image
Stephen Smith • Edited

There are 7 primative data types in JavaScript as listed here Data Types. Arrays, Objects are not primatives, they are a part of the Standard built-in objects
which there are more than 8. You have things such as Map, Set, WeakMap, WeakSet, Proxy, Buffers (though only on server side, I mean the Buffer not ArrayBuffer or the like), etc... This was a genuine attempt to compare the differences and similarities between PHP and JavaScript. Maybe include some code examples, because to a beginner this is just words on the screen and have not substantive value.

jonrandy profile image
Jon Randy 🎖️

They are : Boolean, Array, object, number, undefined, null, string, Bigint

You missed Symbol

justin_okpara_23ffc03ea1e profile image
Justin Okpara

Yeah, totally forgot, thanks for the update.