believe everything on the internet.
The First National Confederate Flag is know as the stars an bars. which has a blue field in the upper left corner and a red bar, a white bar and a red bar. This was a national flag of the Confederate States of America This similarity to the union flag lead to the creation of the ANV (Army or Northern Virginia) Battle flag, which is the first picture in your post.
The second picture is the Third National Flag of the Confederates States of America, the Second National Flag is the same as the third, it just did not have the Red Bar on the end, the reason it was changed, was that when it was limp on the flag staff, it could be mistaken for a flag of truce.