An el­lip­sis (plural el­lipses) is a se­quence of three dots used to in­di­cate an omis­sion in quoted material.

The el­lip­sis is fre­quently ap­prox­i­mated by typ­ing three pe­ri­ods in a row, which puts the dots too close to­gether, or three pe­ri­ods with spaces in be­tween, which puts the dots too far apart.

So use the el­lip­sis char­ac­ter, not the approximations.

Should you put word spaces around an el­lip­sis? As with the em dash (see hy­phens and dashes), that’s up to you. Typ­i­cally you’ll want spaces be­fore and af­ter, but if that looks odd, you can take them out. If there’s text on only one side of the el­lip­sis, use a non­break­ing space on that side so the el­lip­sis doesn’t get sep­a­rated from the text.

“But my boss makes me use pe­ri­ods with spaces in be­tween.” Then let’s min­i­mize the harm. The prob­lem with us­ing pe­ri­ods with word spaces is that it in­vites your word proces­sor to break the el­lip­sis across dif­fer­ent lines or pages, like so:

To keep the dots to­gether, make your el­lip­sis out of three pe­ri­ods with non­break­ing spaces in be­tween. Also use non­break­ing spaces on the ends un­less there’s text on both sides. This en­sures that the pe­ri­ods be­have like a sin­gle unit of punctuation.