what is the difference between

Scenario 1:

```
if (condition)
{
   do something;
}

else
{
   if(condition)
    {
        do something;
    }
}

```

Scenario 2:

```
if (condition)
{
   do something;
}

else if(condition)
{
   do something;
}

```

Scenario 3: 

```
if (condition)
{
}

else
{
  do something;
}

```

question 1:
I have seen 1st and 2nd scenarios in some tutorials why do u have to explicitly define the condition for else .? It would automatically go to else condition when if condition is false why do u have to again specify the condition ??

question 2:

What is the difference between scenario 1 and scenario 2 ??