Salford Piano Studio
A dot adds half the value of the note it is attached to.
It is always written after the note (to its right).

Let’s have a look at some examples
Dotted Minim
a dotted minim (3 beats) = minim (2 beats) + crochet (1 beat)

Similarly, we can think of the dotted minim (3 beats) as made of 3 crochets (1 beat + 1 beat + 1 beat)

Dotted Crochet
A dotted crochet = crochet (1 beat) + quaver (half a beat)

Once again, we can think of it as made of 3 quavers.

Dotted Quaver
A dotted quaver = quaver + semiquaver

Likewise, can also be thought of as 3 semiquavers inside the quaver

Example
In this melody from Beethoven’s “Eroica” symphony, the 2/4 time bars are made of dotted crochets and quavers.
