- string (text) such as varchar in SQL
- integers (whole numbers such as 1 or 8)
- floating point or decimal numbers (numbers with a decimal point e.g. 1.835)
- boolean (representing yes/no, true/false or on/off)
There are many others so make sure you are using the correct data type when you use SQL and be aware of the concept that many programmers have to worry about data types but you don't for Web development programming. The SQL data types you have not used yet can be easily researched when you need them.