## What is Computer? History of Computer.

 Image Source:- Quora

Hey Friends in today's era, computers or laptops are the basic components which are used normally in all the workplaces such as schools, colleges, hospitals, laboratories, companies, etc. Today Computer is the basic thing in our day to day life. Human life has become very easier with computers. Because you can do your work within second with the help of computer and internet. Such as sending an important file to someone. Just open your laptop and mail the document within seconds.  So today we are going to discuss computers and their different types. And also the basic computer required for computers. So Let’s Begin…

# What is Computer?

Many people use a computer daily for some work. But do you know about computers? what is a computer? I bet many people didn’t know about it. So Basically, A Computer is a programmable electronic device, which is used to perform mathematically or logically operations. A user input data through any input device after that a set of instruction process and provide the result of it as “Output”.

A Computer can process arithmetical as well as logical calculations. Arithmetically operation such as +,-,/,* etc and logical operations are  a>b, a<b, a>=b, etc. These operations are processed by a set of instruction written on it.

In simple words, A computer is an electronic device that accepts data as input and processes it, and gives the result of that input as output.

# Father of Computer and The first computer

Do You know that the father of computers is Charles Babbage. Because it is believed that the first computer was invented by him. Analytical Engine is considered as the first computer which is invented by Charles Babbage was first described in 1837

# From an Electronic Device to Computer.

Now let all these aside and tell me that do you know how an electronic device gets the name computer?

The term Computer is derived from the Latin word “Computare” which means calculate.

## What is Address Bus, Data Bus & Control Bus in Computer?

If you’re reading this tutorial by skipping the previous tutorial then I strongly recommended to you to learn first previous tutorial. In the Previous tutorial, we had discussed the basic concept of Buses. We can also say that previous tutorial is introduction tutorial about buses…

Let’s come on topic…Today I am going too described Address Bus, Data Bus, and Control Bus.

### What is the Address Bus?

The address bus is used by the CPU to send the address of the memory location or the input/output port that is to be accessed at the instant. It is a unidirectional bus i.e. the address can be transferred in one direction only and that is form CPU to the required port or location.

Whether it is a read operation or write operation the CPU calculates the address of the required data and sends it on the data bus for the execution of the required operation. The maximum number of memory locations that can be accessed in a system is determined by the number of lines of an address bus.

An address bus of n lines can be addressed at the most 2n locations directly. Thus a 16-bit address bus can allow access 2 16 bit or 64 K Byte of memory.

People Also Read:- What is an Application Software? And It's Need.

## What is Data Bus?

A data bus is used to carry the data and instructions from the CPU to memory and peripheral devices and vice versa. Thus it is a bidirectional bus. It is one of most important parts of the connections to the CPU because every program instruction and every byte of data must travel across the bus at some point.

The size of the data bus is measured in bits. The data bus size has much influence on the computer architecture because the important parameters of it like word size, the quantum of data etc. are determined and manipulated by the size of the data bus.

Generally, a microprocessor is called n-bit processors. Thus as the CPU became more advanced, the data bus grew in size. A 64-bit data bus can transfer 8 bytes in every bus cycle and thus its speed is much faster as compared to the 8-bit processor that can transfer one byte in every bus cycle.

### What is a Control Bus?

A control bus contains various individual lines carrying synchronizing signals that are used to control. Various peripheral devices connected to the CPU. The common signals that are transferred to the control bus from CPU to devices and vice versa are memory read, memory writes, I/O read, I/O write etc.

Signals are designed, keeping in mind, the design philosophy of the microprocessor and the requirement of the various devices connected to the CPU. So different types of the microprocessor have different control signals. See Below for better understanding.

 Image Source Book

Hopefully, you guys did still find this information is useful for you. If you have any doubt or question about this tutorial then let me know through your comment. And don’t forget to share with other computer lovers.
Have a Good Day!!!
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## CSS Position Properties :- CSS Tutorials

CSS Position

The CSS Position Property is used to position any Html element before or after any Html element you want. You can place Html element anywhere you want. You can set the position of Html element by using top, bottom, left, right properties. This property is used when you set the position property of the element first.

Basically, The CSS Position property has 4 basic Parts:-

• CSS Static Positioning
• CSS Fixed Positioning
• CSS Absolute Positioning
• CSS Relative Positioning

CSS STATIC POSITIONING

This is by default the position of the Html element. They appear normally on your web pages. They didn’t affect any positioning on your webpage.

CSS Fixed Positioning

This property is used to fix the position of the Html element on your web pages. When you apply this property to the Html element they fixed their position. It doesn’t move even you scroll your window screen. Let see an example to clear this property.

Example:-

<!DOCTYPE html>
<html lang="en">
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Position in CSS </title>

<style>
div{
border2px solid black;
height320px;
width420px;
marginauto;
overflowscroll;
}
h1{
colorred;
positionfixed;
left320px;
}
</style>
<body>
<div>
<h1> Tokyo Olympics 2020</h1>
<p>Lorem ipsum, dolor s elit. Corporis explicabo eveniet repellat?</p>
<p>Lorem ipsum, doicing elit. Corporis explicabo eveniet repellat?</p>
<p>Lorem ipsum, dolor sit asicing elit. Cobo eveniet repellat?</p>
<p>Lorem ipsum, dog elit. Corporis explicabo eveniet repellat?</p>
<p>Lorem ipsum, dolor sit amet g elit. Corpori eveniet repellat?</p>
<p>Lorem ipsum, dolor sit ameorporis explicabo eveniet repellat?</p>
<p>Lorem ipsum, dolor sit amet  Corporis explicabo eveniet repellat?</p>
</div>
</body>
</html>

Output :-

CSS Relative Property

The relative positioning property is used to set the element relative to its normal position.

Example:-

<!DOCTYPE html>
<html lang="en">
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Position in CSS </title>

<style>

h1{
colorred;
positionrelative;

}
</style>
<body>
<div>
<h1> Tokyo Olympics 2020</h1>
<p>Lorem ipsupisicing elit. Corporis explicabo eveniet repellat?</p>
<p>Lorem ipsum,adipisicing elit. Corporis explicabo eveniet repellat?</p>
<p>Lorem ipsum, adipisicing elit. Corporis explicabo eveniet repellat?</p>
<p>Lorem ipsum, dolor elit. Corporis explicabo eveniet repellat?</p>
<p>Lorem ipsum, dolor sit . Corporis explicabo eveniet repellat?</p>
<p>Lorem ipsum, dolor  Corporis explicabo eveniet repellat?</p>
<p>Lorem ipsum, dolor  Corporis explicabo eveniet repellat?</p>
</div>
</body>
</html>

Output:-

CSS Absolute Positioning

In this property, the position is relative to its first position. In other words, It is positioned relative to its closest positioned ancestor. Let’s see through an example below:-

Example:-

<!DOCTYPE html>
<html lang="en">
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Position in CSS </title>

<style>
body{
background-colorlightblue;
}
h2{
positionabsolute;
background-colorlightcoral;
colorblue;
top200px;
left100px;
}
h3{
coloryellow;
background-colorcornflowerblue;
}
h1{
colorred;
background-colorcornsilk;
positionabsolute;
top250px;
left300px;

}
</style>
<body>
<p> It started from top left cornor. </p>
<h3> This is a heading without positioning.</h3>
<h1> This is a Heading 1. </h1>
<h2> This is a Heading 2. </h2>
</body>

</html>

Output :-

## CSS Fonts Properties :- CSS Tutorials

Hey Friends, Today we are going to discuss CSS fonts. But before starting the article, I have to clear a thing that, font is part of both Html and CSS. In Html, we just placed our font and after it, we apply the property of the font using CSS. In a website, font played a very important role to look your website more beautiful and stylish.  So let’s started our today’s topic CSS Fonts.

CSS Fonts

CSS Fonts property is used to control the texture of your website. By using this property you can change anything of your font just like text, font-family, bold, italic, color, and many more thing. We can see these properties one by one in the below examples. But before it lets me cover some important font attributes. These are listed below:-

• CSS Font Color
• CSS Font Family
• CSS Font Weight
• CSS Font Style
• CSS Font Size

CSS Font Color

This Font CSS Property is used to change the color of the text of your web pages. You can change the text color in three different ways. These different ways are:-

• By Color Name
• By RGB Value

In the above example, we define all 3 ways to change text color.

Example:-

<html>

<style>
h1{
colorred;
}
h2{
color:  rgb(12398235);
}
h3{
color#33FFDA;
}

</style>
<body>
<h1> This is Heading Number 1. </h1>

<h2> This is Heading Number 2.</h2>

<h3> This is Heading Number 3. </h3>
</body>
</html>

Output:-

CSS Font Family

This font CSS property is used to change the font of your web pages. You can provide any type of value to it. Just like: - Arial, Times New Roman, Monospace, Arial Bold, etc.

Example:-

<html>
<style>
h1 {
font-familysans-serif;
}

h2 {
font-familyArial Impact, Haettenschweiler, 'Arial Narrow Bold'sans-serif;
}

h3 {
font-familyImpact;
}
</style>

<body>
<h1> This is Heading Number 1. </h1>

<h2> This is Heading Number 2.</h2>

<h3> This is Heading Number 3. </h3>
</body>

</html>

Output:-

CSS Font Weight

This Font Property is defined. how bold your text is. There are some different values by applying it you can change the font-weight accordingly to you. You can also use some predefined values such as Bold, Normal, Bolder, Light, etc.

Example:-

<html>
<title> This is title. </title>

<body>
<p style="font-weight: lighter;"> This is 1st Paragraph. </p>
<p style="font-weight: bolder;"> This is 2nd Paragraph. </p>
<p style="font-weight: 800;"> This is 3rd paragraph. </p>
</body>
</html>

Output:-

CSS Font Style

This property defines that how your text will appear on your webpage. It may be normal, bold, italic, oblique, etc.

Example:-

<html>
<title> This is title. </title>
<style>
#para1{
font-styleitalic;
}
#para2{
font-stylenormal;
}
#para3{
font-styleoblique;
}
</style>
<body>
<p id = "para1"> This is 1st Paragraph. </p>
<p id = "para2"> This is 2nd Paragraph. </p>
<p id = "para3"> This is 3rd paragraph. </p>
</body>
</html>

Output:-

CSS Font Size

It define the size of the font appear on your webpages. It should be small, normal, medium, large.

Example:-
<html>
<title> This is title. </title>

<body>
<p style="font-size:small;">  This font size is small</p>
<p style="font-size:large;">  This font size is large. </p>
<p style="font-size:200%;">  This font size is set on 200%. </p>
</body>
</html>

Output :-