What does a bug mean in the computer?

What is Bug?

Bugs are small errors in computer programming. Bugs arise from mistakes and errors made in either the design of a program or it's source code. A few are caused by compilers producing incorrect code. Bugs may have subtle effects or cause the program to crash or freeze the computer. Every software bug has a life cycle. The moment a bug is discovered it is in the 'new' state. When it is reported to a developer the state becomes ' assigned '. If the issue is fixed it is marked as fixed. The bug is not a virus. A computer virus is a software designed to be annoying or destructive. However, a bug is only s mistake in the code. It is rather a coding error that cannot be transmitted from one computer to another.

Where does the term computer bug come from?

During World War II, the US military had a computer. The computer size was equal to a room. When it was damaged, a woman named Grace Hopper discovered the problem. An insect was found dead inside the computer. The woman wrote in the register that the bug had been found. It's dead body was posted on the register. Later technical glitches became known as bugs. After calling the annoying insect a bug, technical interruptions began to be called a bug. Even the world's first computer programmer began to used the word bug. Thomas alwa Edison also called technical glitches bugs.

Classification of bugs

Some classification of bugs are token error, syntax error, syntax constraint error, execution error, intent error.

Token error - A token errors occurs whenever program contains a word or symbol that is not in javas vocabulary.

Syntax errors - Even though the java compiler may recognize every token in a program still may contain a syntax error.

Syntax constraint errors - These errors occur when the java compiler cannot determine the meaning of a program. Sometimes a sentence might seem syntactically correct but meaningless.

Execution errors - Execution errors occur when the java run time system is executing a program and discovers that it cannot legelly carry out one of our instructions.

Intent errors - It is most insidious because neither the java compiler or run time system can detect this type of error when it occurs.

Common classification of software bugs are,

1) Functional defects

2) performance defects

3) usability defects

4) compatibility defects

5) security defects

10 famous bugs in the computer world

1) Ariane 5 rocket failure (1996)

2) Y2K bug (1999)

3) patriot missile failure (1991)

4) AT&T(1990)

5) Gangnam style broke YouTube (2012)

6) Mariner one software bug(1962)

7) NASA'S Mars climate orbiter (1988)

8) Pentium FDIV bug (1993)

9) PayPal error (2007)

10) windows calculator bug (1989)

Debugging

The process of finding and fixing bugs is termed debugging.

In software development the developer can locate the code error in the program and remove it using this process.

Different types of Debugging for different operating system

a) For Linux and Unix operating systems GDB is used as a standard debugger.

b) For Windows OS, the visual Studio is a powerful editor and debugger.

c) For Mac OS, LLDB is a high level debugger.

d) intel parallel inspector is used as a source of debugging for memory errors in C/C++ operations.

What are the steps to debugging

1) identify

2) isolate

3) Fix

4) review

5) conclusion