I am a novice and have heard the term "good bishop vs bad bishop" and I needed some clarification. 

Lets say I'm playing white and the majority of my pawns are on light squares. By doing this, my dark squares are now weak and can be infiltrated by my opponent's dark square bishop. Therefore my dark square bishop is considered the "bad bishop". Is that correct?

If that's the case, I had a follow up question. Using the same example, after exchanging my dark square bad bishop, my light square bishop will now be blocked by all the pawns on light squares. How does this constitute as a good bishop?

I understand that throughout the game, my pawns can obviously move to dark squares but I just wanted some clarifcation.

I know there are exceptions to the rule but a general explanation would be greatly appreciated. Thanks!

At least half the consideration is the mobility of the bishop. So you've gotten it backwards. If all your pawns are on light squares, your dark square bishop is your "good" bishop, and the light square bishop is the "bad" bishop. All those light square pawns impede your light square bishop.

Yes, another part of the equation is redundancy and weakness. All pawns on light squares makes the light square bishop a little redundant (at least in defense of pawns) and the dark squares are your weaker color, so it can be important to keep the dark square bishop.

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Ok, now some exceptions.

A "bad" bishop that isn't stuck behind the pawns may be an active "bad" bishop. This may be because either you move the pawns off that color, or the bishop maneuvers around to the front of the pawns. An active "bad" bishop can be a good piece that you don't rush to trade away. Basically activity is more important than the good/bad label.

A "bad" bishop that's defending an important point, piece, diagonal, etc, may be a very valuable piece even though it has no other prospects in the position. Usually being stuck in passive defense is bad, but again, it's not so bad to be "stuck" defending critical points.

Sometimes, I say, sharply, "BAD bishop! ... BAD bishop!" (It never seems to listen.)

The Term

Good bishop vs Bad bishop

is considered to be an out dated terminology.

Modern Chess has changed the words to Active Bishop vs Inactive Bishop.

However, when the Terminology was first invented.

Good bishop vs Bad bishop was based on the center pawns.

I will show an example below:

Now in the above diagram.

Blacks Dark square bishop is considered the Good Bishop.
Blacks Light square bishop is considered the Bad Bishop.

When you look at the below picture you can see they "USED TO" call it under such terms.

The black bishop on c8 is hitting the black e6 pawn.

The e6 pawn can't move right now.

Which will result in a long term problem for black.

The reason they called it a bad bishop is because blacks c8 bishop is not hitting alot of squares.

You can see it only hits the d7 square.

The pawn on e6 is really stopping the bishop from getting influence right now.

On the other hand:

Blacks dark bishop is got alot of options.

As soon as the c5 pawn moves which it eventually will in this line.

The dark bishop will be zooming all the way down to a3

Obviously the c5 pawn can exchange itself to open up the dark bishop.

The e6 pawn can't exchange itself so the light bishop will have problems.

In the French you sometimes hear them say the light square bishop is the problem piece which now you can see why.

Now if we flip the board.

We can try and figure out which one is whites bad bishop and which one is whites good bishop.

In the above picture.

The white dark square bishop on c1 is considered to be the bad one.

The reason why is because the center pawns are on dark squares and the bishop is a dark bishop.

The white light square bishop on f1 is considered to be the good one.

The white light square bishop will have more active possiblities.

The center pawns being on the same color as the dark bishop will harm it from having tons of influence.

Obviously the dark square bishop does have a nice view to h6.

However, if it moves to like e3 for example it would not have any influence on the queen side. The d4 pawn would be blocking its view to the queenside.

In comparision if the light square bishop was to go to d3 it would influence both sides of the board.

These good bishop vs bad bishop terms were used a long while until it started to create confusion.

Which is why they changed it to Active Bishop vs Inactive Bishop

The confusion which started to happen is when you get the "Bad Bishop" Outside of the pawn chain.

Which will result into a Good "Bad Bishop"

The pawns are still on the same color so the bishop will always be considered bad lol. However when the bishop is outside of the pawn chain and is active it is doing a good function or it is a good piece.

Which confuse people when you say you have a Good Bad Bishop or Good Bishop for short.

To give an example of this we can take a look at the Italian Game.

In the below picture the bishop on the same color as the center pawns is considered to be the bad bishop.

Hopefully you can guess the Light square bishop is the bad bishop here.

The Dark square bishop is the good bishop here.

The reason they started changing the Terminology is because people get confused with the terminology and the function!

The Terminology would state the light square bishop will forever be the bad bishop in this position because the center pawns being on light square.

If we follow the above terminology in green. Some players would be compelled into trading the light square bishop thinking to themelves as if they are doing something good.

However, seeking trades of the light square bishop in this position would be a mistake!

The Function/Activity the Light square bishop has outside of the pawn chain is Wonderful! The Light square bishop is hitting f7. Which makes it a Good piece.

Since the piece is a "bishop". People will call it a Good bishop based on its activity; however, we both know it is a Bad bishop because of the center pawns being on the same color.

To end all of the confusion and to help prevent players from doing terrible bishop trades!

People now base the bishops on Active vs Inactive.

In this position the bishop on c4 is a very Active Bishop making it a great piece. One which you should not exchange on a wimp.

You can only image how many players made bishop trades using the Terminology of getting rid of the bad bishop. Only for it to backfire on them causing them to lose the game!

Before Making any trades always ask yourself is this trade benefiting me!

Is my bishop active?

If the bishop is active and doing something than keep it!

In the above example the bishop on c4 is hitting f7. It is doing a very useful function it in fact is better than the bishop on c1 in this position.

The bishop on c1 is hitting h6 no black piece or pawn is on h6.

If we was to use the old terms here we would say the Bad Bishop is putting the white Good Bishop to utter shame in this position lol.

much appreciated everyone for the responses and the diagrams! 

It's not outdated terminology. Generally I would ignore X_PLAYER_J_X , he writes a lot and uses diagrams, so the temptation is to think it's useful when it's not.