Run commands to access the control panel in windows Xp

                Type these commands in Run to access the items in the control panel in windows Xp.

• Add/Remove Programs - appwiz.cpl 
• Date/Time Properties control - timedate.cpl 
• Display Properties control - desk.cpl
• Internet Properties control - inetcpl.cpl
• Mouse Properties control - main.cpl
• Multimedia Properties control - mmsys.cpl 
• System Properties control - sysdm.cpl

Changing mouse cursor in Windows Xp

The mouse cursors are yet another item that is saved in the Theme file. Many different pointer schemes are included with Windows XP.
To get your cursors set perfectly for your Theme file, do the following:
1. Click the Start button and select Run.
2. Type main.cpl and click OK to open up Mouse Properties.
3. Next, click the Pointers tab.
4. Once you are there, you have two options to customize the cursors: You can use the drop-down Scheme box to change all of the pointers at once to different styles, by selecting a different cursor scheme from the list.When you select the different schemes, all of the cursors will change automatically. Alternatively, if you do not like the cursor schemes, you can individually select a cursor from the customize box list by scrolling through the list and selecting the cursor you want to change. Then, hit the Browse button to change it.
5. When you are finished customizing your cursors, just hit the OK button and you are finished.

Changing the system sounds in Windows Xp

                 Changing the event sounds is very simple. Just follow these steps:
 

1. Click the Start Menu and select Run.

 2. Type mmsys.cpl in the box and click OK to launch the system Sounds and Audio Devices Properties.

 3. Once the Sounds and Audio Devices Properties loads, click the Sounds tab.

4. Next, to adjust the sound clip for a specific event, click the event that you want to modify, by navigating though the Program Events box.

5. Once you have an event selected, the Sounds drop-down list will become enabled and you will be able to select the sound clip that you want to use. You can select (None) from the top of the list if you do not want to use a sound for a specific program event. If youcannot find a sound that you like on the list, you can use the Browse button to pick a specific sound file on your computer to use.

6. When you are finished with your changes, just click OK to save.

To make icons on the desktop large

                    The normal size for icons in Windows XP is 32 X 32 pixels.Windows XP also has support for larger icons, which are 48 X 48 pixels.

Follow these steps:

1. Right-click the desktop and select Properties.
2. 2. Click the Appearance tab and then click the Effects button.
3. Check the Use Large Icons box.
4. Click OK to save your changes.
5. Click the OK button again to close display properties.

 

Removing a user name from the Welcome screen of windows Xp

                     The welcome screen of the windows Xp present a list of all of the user accounts on the computer. Windows Xp has a feature to hide the user accounts from the Welcome screen, which we want to use a user account secretly.

                    To hide a user from the Welcome screen, all you have to do is create an entry on the list for the
user you want to hide. Follow these steps to find out how to add a user to the list:

1.  Click the Start button and select Run, then type regedit in the box and click OK.
2.  This will start up the system Registry Editor. Expand the following keys: HKEY_LOCAL_MACHINE, SOFTWARE, Microsoft, WindowsNT, CurrentVersion,Winlogon, SpecialAccounts, and UserList. 
3.  You should now see the list of the account names, and parts of account names, that the system will look for and will hide.To add a name to the list, just right-click and select New, then select DWORD value. A DWORD is a specific data type of an entry in the system registry. In short, the DWORD data type allows an integer value to be stored.
4. When the new key is created, enter in the name of the user’s account as the name of the key. Once you have done this, you can close regedit.

               After log off and back on or reboot, the user will not be displayed on the Welcome screen. If you ever want to log into the account that you hid from the Welcome screen, just press Ctrl+Alt+Delete on your keyboard once, twice, and you will be able to type in the name of the user under which you want to log in. This way, you can hide an account from your family or friends but can still log into it.

                If you ever change your mind and want the account to be displayed on the Welcome screen again, just delete the entry that you made in the list in the System Registry and everything will
be back the way it was.

Bits and Bytes

Both RAM and hard disk capacities are measured in bytes.

Bits 

          Computers happen to operate using the binary number system. The reason computers use the binary number system (base-2 system) is because it makes it a lot easier to implement them with current electronic technology. The word bit is a shortening of the words "Binary digIT." Whereas decimal digits have 10 possible values ranging from 0 to 9, bits have only two possible values: 0 and 1.
           Therefore, a binary number is composed of only 0s and 1s, like this: 1010.
The binary number 1010 is?
(1 * 2^3) + (0 * 2^2) + (1 * 2^1) + (0 * 2^0) = 8 + 0 + 2 + 0 = 10
Decimal and binary looks like this:
0 = 0
1 = 1
2 = 10
3 = 11
4 = 100
5 = 101
6 = 110
7 = 111
8 = 1000
9 = 1001

Bytes

       Bits are rarely seen alone in computers. They are almost always bundled together into 8-bit collections, and these collections are called bytes.

        In the ASCII character set, each binary value between 0 and 127 is given a specific character. Most computers extend the ASCII character set to use the full range of 256 characters available in a byte. The upper 128 characters handle special things like accented characters from common foreign languages.

Standard ASCII Character Set

The first 32 values (0 through 31) are codes for things like carriage return and line feed. The space character is the 33rd value, followed by punctuation, digits, uppercase characters and lowercase characters.

0 NUL
1 SOH
2 STX
3 ETX
4 EOT
5 ENQ
6 ACK
7 BEL
8 BS
9 TAB
10 LF
11 VT
12 FF
13 CR
14 SO
15 SI
16 DLE
17 DC1
18 DC2
19 DC3
20 DC4
21 NAK
22 SYN
23 ETB
24 CAN
25 EM
26 SUB
27 ESC
28 FS
29 GS
30 RS
31 US
32
33 !
34 "
35 #
36 $
37 %
38 &
39 '
40 (
41 )
42 *
43 +
44 ,
45 -
46 .
47 /
48 0
49 1
50 2
51 3
52 4
53 5
54 6
55 7
56 8
57 9
58 :
59 ;
60 <
61 =
62 >
63 ?
64 @
65 A
66 B
67 C
68 D
69 E
70 F
71 G
72 H
73 I
74 J
75 K
76 L
77 M
78 N
79 O
80 P
81 Q
82 R
83 S
84 T
85 U
86 V
87 W
88 X
89 Y
90 Z
91 [
92 \
93 ]
94 ^
95 _
96 `
97 a
98 b
99 c
100 d
101 e
102 f
103 g
104 h
105 i
106 j
107 k
108 l
109 m
110 n
111 o
112 p
113 q
114 r
115 s
116 t
117 u
118 v
119 w
120 x
121 y
122 z
123 {
124 |
125 }
126 ~
127 DEL

Lots of Bytes

• Kilo (K) =2^10.
• Mega (M)=2^20.
• Giga (G)=2^30.
• Tera (T)=2^40.
• Peta (P)=2^50.
• Exa (E)=2^60.
• Zetta (Z)2^70.
• Yotta (Y)=2^80.