Nikolai - First off, great question. many new designers interested in Typography (eg. myself 7 odd years ago) thinks the more fonts you have the more choice you have.

Not really - the more fonts you have the longer it takes to evaluate the possibilities for each project and the more wrong fonts you need to wade through before finding something suitable. In the commercial world time is morning and therefore you are actually restricting the chances you will find a great font inside the deadline!

That being said I would start with a couple of good quality fonts and really know the font inside out before buying more.

Know what the designer intended, know if the target audience is (over)used to the font, what attitude it conveys subliminally. How dark it makes the page, whether it suits looser or tighter leading and what point size is most suitable for different lengths of copy.

Also know how the family fits together. How much emphasis does a bold give to the roman, maybe the black weight will work better, or maybe the italic is different enough for emphasis.

A tiny selection of my workhorse fonts are:
Sans - Frutiger, DIN, Avant Garde
Serif - Minion Pro, Adobe Garamond Pro
Script - Voluta Script, Pilsner (Letterhead Fonts)

PS - If you use InDesign for page layout always try and use OpenType fonts (good quality) and use the extras like ligatures and the correct type of numerals for the task at hand.

I think the catagories are much along Daniel's suggestion but with an addition:

Headline: Fonts that you wouldn't set text in like Brok or Poster by Font Bureau

Promotional: Fonts you might set one or two words in, think Font Diner fonts. These would commonly be seen on packaging or point of sale.

I would try to go for one or two fonts from each stylistic /time period category. This way you can cover most of the different options there are for just about any situation.

Blackletter: Fraktur (Fette Fraktur), Textura (Goudy Text)
Serif: Venetian (Jenson), Transitional (Baskerville), Modern (Bodoni), Postmodern (Eidetic)
Script: a brush script, formal script, and handwriting
Sans: Grotesque (FB Grotesque), Humanist (Gill), Institutional/technical (Helvetica, Eurostyle)
Display: Postmodern/Classic (Mason), Vernacular signage (Los Feliz)
Calligraphic: Uncial (American Uncial) etc. etc.

This is obviously a small list, but you get the general idea, I hope.

This would be my list of fonts that are important enough that everyone should know how to use them well. There are a bunch that I thought about putting on this list, but in the end, learning to use Helvetica means you'll be able to use Univers, etc. as well.

Helvetica (really hard to use well, but man it looks great when it's done right, ala Designer's Republic)

Garamond (classic workhorse)

Caslon (the other classic workhorse)

Bodoni (the other, other classic workhorse)

Futura (simple and perfect, much easier to get right than Helvetica)

DIN (for any sort of industrial-nuanced application this font looks great, but it's a bit tough to use well)

Gill Sans (humanistic sans serifs have always been easy for me to use, but they do seem to require a careful eye in the letterspacing)

Optima (the subtlties of this face make is difficult to use, and it's horrible mis-use as "the hospital font" makes good uses of it breathtaking)

FF Meta (one of the best designed typefaces of the last 10 years, and remarkably easy to use)

ITC Century (a retro-classic, hard to use well)

Franklin Gothic (not quite geometric, not quite humanistic, more personality than Helvetica, less than Gill)

You've alluded to an interesting question:

What makes a font "easy to use"?

(If this is juicy enough it should get its own thread.)

hhp

What term are you? Im 6th term graphic design at art center. great question btw.

Thanks to everyone for the feedback so far.

Well, since you said "know how to use" not "own," I'd include the following (not a complete list)

Gill Sans
It's everywhere. I swear, I'm sick of using it, no matter how nice it is.

Helvetica or Helvetica Neue (complete family)
This includes the extended and condensed weights. Another one that you can't avoid.

Adobe Garamond (Pro, if possible)
I quite like it, and it's common. It presents interesting challenges at smaller sizes, due to its more fragile features, and small x-height.

FF Meta
The ubiquitous Humanist sans. High legibility, 'the next Helvetica' for a while. Unavoidable.

Futura (not sure which is best)
Classic geometric sans. Very common.

Adobe Minion Family (Pro if possible)
Solid, a workhorse of book typography. See Bringhurst's Elements of Typographic Style. Very comprehensive family.

Bodoni (again, not sure which version, maybe not Bauer as it's got very hight contrasts)
The archetypical Neo Classical font. Haven't seen it around as much lately (at least in my line of work), but I think it's a must.

Frutiger and Univers Families
Adrian Frutiger's classic sans fonts. More personality than Helvetica, less than Meta (IMO). In short, Frutiger is friendly and Univers is serious. Another pair you can't avoid.

A Gothic (Bell, Trade, Franklin)
I saw a lot of these when I was in school. They seem to be waning again, but familiarity with them is important.

These stick out in my mind as "need to know". There are so many others that I see a lot, like Mrs. Eaves. These are all very good to know, but aren't on my top-tier list of ones you need to know how to work with. Again, this is a partial list.

Hrant,

For me, easy to use type means that no matter what size, leading, letterspacing, etc. the setting just "feels" right. It looks professional, it looks appropriate.

For me, Helvetica is a typeface I just don't have the hang of yet. I use it very infrequently, but for some reason, it just never turns out right. Either I set it too large, or space it out too much, or too little. There's a middle ground that I can't seem to hit. There's a few other typefaces like that for me as well.

However, Futura seems to just set perfect, with little tweaking. When I set 18 point heads with 9 point subs, it looks right. When I letterspace it for effect, it looks right. Meta is the same way. I don't think it's so much the kerning tables, but the character shapes. The challenge with Helvetica is getting over the lack of continuity between letterforms.

I'm sure I could ramble on and on about this.

"See Bringhurst's Elements of Typographic Style."

This is the one occasion where an All Caps, Bold Italic with an underline and a dropshadow might just be appropriate. ;)

This is a book that should be given to every Graphic Design student. If you can't enjoy reading this book you should be made to shift into another course - eg. Graphic Stylist not designer. I don't know how I possibly called myself a designer throwing text onto the page without knowing or realising the subtleties of the craft that is contained within this typographers bible.

Everyone should learn NOT tu use Avant Garde, it

Sean, it seems to me that the easier a font is to use the less focus it has.
For example, a font that looks decent at greatly varying point sizes can't work really well at any.

hhp

>For example, a font that looks decent at greatly varying point sizes can't work really well at any. <

This is the silliest thing I have every heard from you. And there have been a great deal of silly things.

Hector, I think everyone should learn to use Bookman Bold Italic Swash. What a useful text face. And courier is a classic favorite.

James, we just have different ideas of where the threshold between display and text is.

hhp

Hector, I think everyone should learn to use Bookman Bold Italic Swash. What a useful text face. And courier is a classic favorite.


I don

Sorry Hector, it was a poor attempt at making a joke. Bookman Bold Italic Swash has become popular again and I hate that face and its surely not a text face. And who could love Courier its like anti design. I was joking with you because of your remark about Avant Guarde. Maybe if we ignore these faces they will go away.

I whould add Officina Sans and Officina Serif especially for use in cyrillic.

Nevermind Daniel, it

Filosofia is getting around these days...

Bodoni is fun to play around with.

Univers I find great.

TheSans I'm getting into.

Sabon is amazing.

Kottke's silkscreen. Free and good.

Hrant's Mana is some neat stuff, and demonstrates amazing foresight.

Anything made out of real wood. (no fake wood!)

Georgia is fantastic on screen and even in print.

Lucida Grande is my on-screen sans serif choice.

New Century Schoolbook is one of my all-time favorites.

Futura I think is extremely hard to get right. If done well, it's fantastic.

Janson Text is solid.

Some form of Garamond. Preferably a good version. I can't remember what's good. Berthold, maybe?

Galliard is pretty great.


Faces I'm not so thrilled with:

Mason. Nah. Reminds me of Queensryche and only Queensryche.

Anything Spiekermann. Sorry. They look corny. FF Unit as a small text face isn't too bad, but anybody who titles his book stupidly just to include and "fi" ligature rubs me the wrong way. "Find out"?? How about "learn"? (Stop Stealing Sheep and find out How Type Works) The title just doesn't work.

Frutiger is sterile.

Arial. Some Chicago Transit signs are in Helvetica. Some are in Arial. Arial is a disaster. At least Helvetica can do its job.

Verdana. Sorry, Carter.

Copperplate Gothic. Try again.