The Difference Between "Coffee" and "Dinner"
I grew up in rural West Virginia. If you've ever been to West Virginia, you know "rural West Virginia" is redundant because most of WV is rural. It's also culturally the south. When you found someone you were interested in, you asked them out on a date. That usually meant dinner, bowling, mini-golfing, or a movie. That was a date and how you communicated yourself and your interest.
When I moved to California, I kept hearing about taking a girl out "for coffee." That seemed odd to me and I didn't really have a good box to put it in. I later went back to WV for Christmas and realized, outside of gas station coffee, the closest coffee shop was 1.5 hours away. THAT explains why "coffee" wasn't on my grid, but I quickly learned it was on the grid of women around me. In dating, it's not just about what you're doing but what you're communicating to your date. So I started trying to understand.
WHAT'S THE DIFFERENCE BETWEEN "GOING FOR COFFEE" AND BEING "ASKED OUT FOR DINNER"?
What "Coffee" Means
Coffee implies a more casual interest and is low stakes for both parties involved. You ask her out for coffee if you've seen her around or know a little bit about her, but want to get to know her more and see if there's anything there. You show interest but also a desire to keep it light.
What "Dinner" Means
Dinner implies a more serious intent. This communicates you're for sure interested and ready to let her know. Maybe you already know her or maybe you just know you're interested. There's no ring in sight, but there is a higher level of commitment and seriousness here. It's more intentionally showing romantic interest.
After you ask her to "go out for coffee" or if you can "take her out to dinner," she may have questions. She may ask you "what do you mean?" or "is this a date?" Confidently reply. "Yes, I'm asking you out on a date," or "I would like to get to know you better."
Note: Some girls love the word "date" and other girls run from it because it feels too heavy. I wish I could tell you who is who but I usually find out after I ask. I like to say say "date." I'm a man asking a woman on a date. I'm not a boy playing around. I'll use the word. If they seem to be shocked or scared by it, I'll affirm with "No pressure. It'll be low key," so they feel safe, but I want them to know I'm showing up. I think when more men start asking women out for dinner, asking a woman out for coffee won't be as big of a deal.
You set the level of interest based upon the amount of time, energy, and money you're investing in her (and asking her to invest). Consider the difference of time and money between coffee, Applebees, and a "you-better-dress-up restaurant." The point of this is good communication and lowering the stress without over explaining. Dating should be fun. If it's not, you may be doing it wrong. Go find yourself a pretty lady with good character and see if anything’s there. ;)
P.S. If it's coffee or dinner. Pay for hers. You're a gentleman asking a lady out. Pay for hers.