Data types associated to the variables establish the content of data and size of areas used to store data. In VB.NET, the following data types are available for software developer:

• Boolean: True/False values; memory area size varies depending on platform implementation;
• Byte: unsigned integer values; a variable of Byte type refers to a memory area of 1 byte length;
• Char: unsigned integer values associated to symbols; the memory length is 2 bytes;
• Date: date and time values; length of reserved memory is 8 bytes;
• Decimal: signed real values; the memory area length is 16 bytes;
• Double: signed real values represented in floating point, double precision; size of allocated memory area is 8 bytes;
• Integer: signed integer values; the memory area length is 4 bytes;
• Long: signed integer values; the memory area length is 8 bytes;
• Object: address type values that relate objects – reference types: string, arrays, object classes, interface; length of reserved memory is 4 bytes (32-bit platform) or 8 bytes (64-bit);
• SByte: signed integer values; the memory area length is 1 byte;
• Short: signed integer values; the memory area length is 2 bytes;
• Single: signed real values represented in floating point, simple precision; the memory area length is 4 bytes;
• String: unsigned integere values associated to Unicode symbols; each Unicode symbol is reserved on 2 bytes;
• UInteger: unsigned integer values; the memory area length is 4 bytes;
• ULong: unsigned integer values; the memory area length is 8 bytes;
• User-Defined: values defined by developer; length of the memory depends on members defined in User-Defined structure
• UShort: unsigned integer values; the memory area length is 2 bytes;

Variables declared without a data type have associated default type Object. The advantage of this technique consists of writing code faster. Disadvantage is the possibility of slower execution of the application