Perfect Computer Notes

Topic: Explain Different Components of Operating System Q. What is an Operating System? Explain Components of an Operating system. Operating System An operating system is a set of programs that manages all computer components and operations. An operating system works as an interface between the user and the computer hardware. Examples of Operating Systems Some popular operating systems are DOS, windows, Unix, Linux, and OS/2. Without Operating System, a computer cannot do anything. Users interact with the computer through operating system. Operating system acts as an interface between a user and computer hardware. Components of an Operating system An Operating system has many components to manage all resources of a computer system as following: 1.    Process Management CPU can perform one task at one time. If there are many tasks, operating system decides which task should get the CPU first. 2.     Main Memory Management Operating system manages memory (RAM)for

Use Of TR Tag <TR> tag is used to create rows in HTML Tables. <TR> is the opening tag to start a row and </TR> is a closing tag to end a row. You can place pairs of <td>...</td> tags to create data cells in a row within the <tr>...</tr> tags. for example to create a row with only one cell containing data "Apples", we will use the following html code.and Mangoes respectively: <tr> <td>Apples</td> </tr> Apples If you want to create a row with two cells containing data "Apples" and "Mangoes" respectively, we will use the following html code. <tr> <td>Apples</td> <td>Mangoes</td> </tr> Apples Mangoes You canm also create a header row with the help of <TR> tag and <TH> tags. For example, to create a header row with two header cells with contents "Employee" and "Salary", we will use the following HTML co

Border: It is used to specify a border and its thickness for a table. Cellspacing: It is used to specify the distance between adjacent cells in a table. Cellpadding : it is used to specify the distance between a cell and cell contents in a table. Width : It is used to specify width of a table in pixels or as percentage to screen width. Align : It is used to specify the horizontal alignment of a table. Possible horizontal alignment values are "left", "right" or "center". Valign : It is used to set the vertical alignment of a table as "top", "bottom" or "middle". Bgcolor : It sets the background color of a table. You can specify color names or hex values for the color. Example of table with border=1, width=200 and align=center attributes HTML Coding: <table border="1" width="200" align="center"> <tr> <th>Book</th><th>Price($)</th> </tr> <