1. Syntax errors
Each programming language has a character set and certain rules for programming. For example, each language has certain rules for combining characters into words, for variable types and names etc. If these rules are violated, they result in syntax
errors. Syntax errors can be detected at the time of compiling.
2. Logical errors
This type of errors occurs due to error in processing data. For example, to find the value of a purchase by a customer, the program must find the product of the unit price and the number of units purchased by the Customer. If the program finds the
sum of these two numbers, it results in logical error.
3. Run-time errors
These errors occur only when the program is executed. So, they are called run-time errors. For example, a program may try to open a file which is not created. Since it needs that file for input or output operation, the program cannot complete its execution.