This allows MTS to reuse database connections. Database 
connections are put to "sleep" As opposed to being created 
and destroyed and are activated upon request.

Apartment model threading

apartment threading and single threading. by vb works on 
apartment threading, completely not support to single 
threading.

To create a remote instance of a script component, call the 
CreateObject method, passing it the name of the remote 
computer as a parameter. 
If the remotable attribute of a script component's 
<registration> element has been set to "true,"
the script component can be instantiated remotely from 
another computer using Distributed COM (DCOM).

Both computers must have basic DCOM installed. Note   The 
ability to use CreateObject for instantiating remote script 
components requires Visual Basic 6.0 or later or VBScript 
5.0 or later.
The following Visual Basic example shows how to do this on 
a computer named "myserver":

Set newS = CreateObject("Component.MyComponent", "myserver")
Note   There can be a slight delay when you first 
instantiate a remote script component while DCOM 
establishes communication between the computers.

1. You can specify the machine on which you want to create 
the remote server object in DCOM config ('dcomcnfg').

2. You can specify the machine name when instantiating the 
remote server object. In C you can do this with a call to 
CoGetClassObject or CoCreateInstanceEx (instead of 
CoCreateInstance, which does not allow you to specify the 
name of the machine).
In VB you can specify the name in one of the parameters in 
the call to CreateObject 

Processes communicate with one another through messages, 
using Microsoft's Remote Procedure Call (RPC) technology to 
pass information to one another.There is no difference to 
the caller between a call coming from a process on a remote 
machine and a call coming from another process on the same 
machine.

Multithreaded applications must avoid two threading 
problems: deadlocks and races.A deadlock occurs when each 
thread is waiting for the other to do something

i don kno

Dim obj as OBJ.CLASS with either
Set obj = New OBJ.CLASS or
Set obj = CreateObject(?OBJ.CLASS?) or
Set obj = GetObject( ,? OBJ.CLASS?)
or
Dim obj as New OBJ.CLASS

Set object = Nothing 
ensure the object is release from the memory.

If this object is a form, you can add set myform = nothing 
and Form_Unload() event.Maintain a habit of remove the 
object by using set object = nothing which will benefit at 
last. Visual Basic is supposed to automatically release 
objects when they go out of scope. To free up some memory 
usage, you can set the object to nothing.

Occurs before a form or application closes. When an MDIForm 
object closes, the QueryUnload event occurs first for the 
MDI form and then in all MDI child forms. If no form 
cancels the QueryUnload event, the Unload event occurs 
first in all other forms and then in an MDI form. 
When a child form or a Form object closes, the QueryUnload 
event in that form occurs before the form's Unload event.

Classes and objects are separate but related concepts. 
Every object belongs to a class and every class contains 
one or more related objects.1)A Class is static. All of the 
attributes of a class are fixed before,during, and after 
the execution of a program. 
The attributes of a class don't change.The class to which 
an object belongs is also (usually) static. If a particular 
object belongs to a certain class at the time that it is 
created then it almost certainly will still belong to that 
class right up until the time that it is destroyed.
2)An Object on the other hand has a limited lifespan. 
Objects are created and eventually destroyed. Also during 
that lifetime, the attributes of the object may undergo 
significant change.So basically the difference between a 
class and an object is that a class is a general 
concept while objects are the specific and real instances 
that embody that concept. When creating an object oriented 
program we define the classes and the relationships between 
the classes . We then execute the program to create, 
update, and destroy the objects which are the specific
realization of these classes.

A class is a template . An object is an instance of a class.

LIST INDEX::
Returns or sets theindex of the currently selected item in 
the control. Not available at design time.Default LIST 
INDEX IS -1 for ComboBox, DirListBox, and DriveListBox 
controls

TAB INDEX::
Returns or sets thetab order of most objects within their 
parent form.Visual Basic automatically renumbers the 
TabIndex of other controls to reflect insertions and 
deletions. You can make changes atdesign time using 
theProperties window or atrun time in code.The TabIndex 
property isn't affected by the ZOrder method.

A LISTBOX CONTROL displays a list of items from which the 
user can select one or more. If the number of items exceeds 
the number that can be displayed, a scroll bar is 
automatically added to the ListBox control.
A COMBOX CONTROL combines the features of a text box and a 
list box. This control allows the user to select an item 
either by typing text into the combo box, or by selecting 
it from the list.
DIFF::Generally, a combo box is appropriate when there is a 
list of suggested choices, and a list box is appropriate 
when you want to limit input to what is on the list. A 
combo box contains an edit field, so choices not on the 
list can be typed in this field.

Embedding objects - 
*******************
When you embed an object, a copy of the object is inserted 
into the destination document. There's no link to the 
original file. When you change information in the 
source document, no changes will be reflected in the 
destination document. The actual data for the object is 
stored within the destination file. To make changes to the 
embedded object, double click it and it will launch the 
original application the source file was in.  
Linking objects -  
*****************
Information is updated when you modify the original source 
file when you use a linked object. This dynamic updating is 
very handy for things such as the aforementioned monthly 
report. You can open up the Excel spreadsheet that is 
referenced within your Word document.Make changes 
to the spreadsheet, close Excel, and when you open your 
Word document... viola! The changes are already there. If 
that object is linked to ten other Word files, the changes 
are already in those ten files, too!
actually linking or embedding an object is fast and easy.

This allows MTS to reuse database connections. Database 
connections are put to ?sleep? as opposed to being created 
and destroyed and are activated upon request.
Object pooling is an important design concept required for 
high-performance applications.
A performance optimization based on using collections of 
preallocated resources, such as objects or database 
connections. Pooling results in more efficient resource 
allocation.

The set of public variables, methods, properties, and 
events described in a class module define the interface for 
an object. The interface consists of the object members 
that are available to a programmer who's using the object 
from code.<=====>
You can create private variables, methods, properties, and 
events that are used by other procedures within the class 
module but are not part of the object's public interface. 
Additionally, constants user-defined types, and Declare 
statements within a class module must always be 
private.<====>
The Friend keyword makes a procedure private to the 
project: The procedure is available to any code running 
within the project, but it is not available to a 
referencing project. 

Connect

The sizing behavior of the image control differs from that 
of the picture box. It has a Stretch 
property while the picture box has an AutoSize property. 
Setting the AutoSize property to True 
causes a picture box to resize to the dimensions of the 
picture; setting it to False causes the
picture to be cropped (only a portion of the picture is 
visible). When set to False (the default)
, the Stretch property of the image control causes it to 
resize to the dimensions of the picture.
Setting the Stretch property to True causes the picture to 
resize to the size of the image 
control, which may cause the picture to appear distorted.

we can access only bitmap files in the Image box but in 
picture box we can access both bitmap & JPEG files.
another difference is image box is having the property of 
Stretch where picture box is not having this property.
so that we can fit the any picture to the reqired size in 
image box.