Computers understand instructions in machine code, which is a binary format consisting of 0s and 1s. Writing programs directly in machine code is challenging for humans, so we typically use high-level programming languages such as BASIC, C++, and Python.
Source Code and Object Code
A program written in a high-level language or assembly language is called the source program or source code. However, source code cannot be executed directly by a computer. It must be converted into machine language, which results in what is known as the object program or object code.
Language Processors
The conversion of source code to machine code is done by special translator software known as language processors or translator programs. There are three main types of language processors:
- Assembler
- Compiler
- Interpreter
Types of Language Processors
Assembler
An assembler translates programs written in assembly language into machine code. The source program, which contains assembly language instructions, is converted by the assembler into object code that the computer can understand and execute.
Compiler
A compiler translates the entire source program as a whole into machine code in one go. Examples of compilers include those for C and C++ languages. If the source code is error-free, the compiler generates the object code. If there are errors, the compiler lists them with line numbers at the end of the compilation process. These errors must be corrected before the compiler can successfully recompile the source code.
Interpreter
An interpreter translates and executes each statement of the source program one at a time. If it encounters an error in a statement, the interpreter stops translating and displays an error message. Only after the error is corrected does the interpreter move to the next statement.
Utility Software
Utility software helps maintain the computer system and ensure it runs smoothly. Many utilities are integrated into the operating system, but additional utility software can enhance reliability and performance. Common types of utility software include:
- Antivirus
- Disk Defragmenter
- Backup Utility
- Compression Utility
- Disk Cleaner
- File Management Tools
Antivirus
Antivirus software detects and removes computer viruses. If a virus cannot be removed, the antivirus software neutralizes it. Types of viruses include:
- Boot Sector Virus: Infects the boot sector, the part of the disk that loads the operating system.
- File Virus: Attaches to executable files, often spreading while other programs run.
- Macro Virus: Targets files with macros, like MS Word’s normal.dot file, affecting document formatting and editing.
- Trojan Horse: Disguised as a useful program but harmful to data, creating bad sectors and corrupting files.
- Worm: A self-replicating program that spreads across networks, disrupting routine services.
Disk Defragmenter
Over time, files on a disk can become fragmented, meaning pieces of a single file are scattered across the disk. This fragmentation slows down file access. A disk defragmenter reorganizes the files, bringing the fragments together to improve access speed.
Backup Utility
This utility creates copies of data stored on a disk or CD. In case of a hard disk failure or other system issues, the backup utility allows users to restore lost files from the backup.
Compression Utility
Compression utilities reduce the size of large files, which saves disk space and makes file transfer across networks faster and more efficient.
Disk Cleaner
A disk cleaner utility scans the hard drive for unused or rarely accessed files that take up space. It prompts the user to delete these files to free up disk space. Important files can be backed up before deletion.
File Management Tools
These tools help users store, index, search, and sort files and folders on their systems. Common file management tools include Windows Explorer and Google Desktop.
Conclusion
High-level programming languages and language processors, including assemblers, compilers, and interpreters, facilitate the creation and execution of computer programs. Utility software plays a crucial role in maintaining system performance and reliability. By understanding and utilizing these tools, users can enhance their computing experience and ensure their systems run efficiently.