When making reference to G-d, we substitute the middle letter 'o' with a dash, a long-standing traditional Jewish custom.
We are charged to treat the name of G-d with reverence, even if expressed in languages other than the vernacular Hebrew. Of the many methods of respect, one is not to erase G-d's name.
While the Name of G-d is fully spelled out in our Torah scrolls and in many books, we prefer to refer to G-d's name in an abbreviated manner in electronic documents for computer displays, a medium that is by nature temporal.
We also make references to G-d as 'Hashem.'
Literally Hashem means 'The Name'
The Torah uses several words when referring to G-d.
Some refer to roles or to aspects of behavior.
In a relative sense, the four-letter name, starting with the Hebrew letter Yud, then the letter Heh, followed by the letter Vav, and ending with a Heh refers to what we can understand as G-d's essence.
Note that this does not refer to G-d's actual essence, for it this is beyond our intellect.
For example, a person may be known as Daddy and/or Hubbie. In actuality, his name may be Joe and that name best refers to his essence.
If the Torah uses one word to reference G-d, we will typically translate it as G-d.
Sometimes, the Torah uses more than one word. For instance, you may find a phrase, Hashem your G-d.
'Hashem your G-d' consists of two words in the Torah. The first is the four-letter name. The second is a word which best translates as 'your G-d.' We would therefore translate the phrase as 'Hashem (The Name) your G-d.'