Web Development Basics: HTML, CSS, JavaScript, PHP, and XML

Q1. Explain <textarea> Tag

The <textarea> tag in HTML is used to create a multiline text input field within a form. It allows users to enter and edit text over multiple lines. The content of the <textarea> element is the initial text displayed in the input field.

<textarea>Initial text goes here</textarea>

In this example, the <textarea> element creates a text input field labeled “Description” with an initial text value and a size of 4 rows and 50 columns. Users

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Understanding Cryptography: From CIA Triad to Encryption Algorithms

Confidentiality, Integrity, and Availability (CIA) Triad

The CIA triad is a model for understanding and discussing security concepts, particularly concerning data security. It emphasizes the negative impacts of security breaches: disclosure, alteration, and denial (DAD).

Confidentiality

Confidentiality, while similar to privacy, is not synonymous. It’s a crucial component of privacy, focusing on protecting data from unauthorized access. In essence, confidentiality means preventing unauthorized access.

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A Comprehensive Guide to ICT Systems: From Hardware to Software

What is an ICT System?

1. Basic Elements of an ICT System

An ICT system comprises four fundamental elements:

  • Hardware: The physical components of a computer system.
  • Software: The set of instructions that tell the hardware what to do.
  • People: The users, operators, and administrators of the system.
  • Data: The raw information processed by the system.

2. Types of ICT Systems

There are three main types of ICT systems:

  • Information Systems: These systems focus on managing data and information. For example, a sports
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Understanding 8085 and 8086 Microprocessors: Architecture, Addressing Modes, and Evolution

8085 Addressing Modes

Addressing modes define how operands are specified in instructions. The 8085 microprocessor utilizes the following addressing modes:

1. Immediate Addressing Mode

Data is embedded directly within the instruction. Instructions with ‘I’ in their mnemonics often use this mode.

Examples: MVI A, 05H; ADI 55H; LXI H, C000H

2. Register Addressing Mode

Data resides in a register, and the instruction references that register.

Examples: MOV A, B; ADD B; ANA C

3. Direct Addressing Mode

The instruction

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PL/SQL Triggers, Procedures, Views, and Concurrency Control in Database Systems

PL/SQL Row-Level Trigger Example

To create a PL/SQL row-level trigger in Oracle that displays the old salary, new salary, and salary difference whenever a modification to the salary column of the emptable occurs, you can follow this syntax:

  1. CREATE OR REPLACE TRIGGER salary_change_trigger
  2. BEFORE UPDATE OF salary ON emptable
  3. FOR EACH ROW
  4. DECLARE old_salary NUMBER; new_salary NUMBER; salary_diff NUMBER;
  5. BEGIN old_salary := :OLD.salary; new_salary := :NEW.salary; salary_diff := new_salary – old_salary; DBMS_
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A Guide to Computer Expansion Cards: Types and Functions

Graphics Cards

Types of Video Memory

DRAM: Were the predominant channels for a long time. Provide low output values.

EDO DRAM: Have been used for quite some time, less expensive than VRAM, is used in middle-low-end cards.

VRAM: You can write to it and read it at the same time. It is much faster than the previous, but memory is a type face.

WRAM: Is a modified version of the VRAM that improves performance and is cheaper.

SGRAM: Currently the most widely used because they offer very good performance. It

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