what's the difference between recommend and suggest?

Answer 1

Not much at all. They're actually synonyms, and mean almost the same thing.

I'd say, if anything, that "recommend" has a bit more authority to it, as if you're speaking from experience, whereas a suggestion is generally more of a thought or idea.

They can be used interchangeably without confusion, though.

SUGGEST:
1. to mention or introduce (an idea, proposition, plan, etc.) for consideration or possible action.
2. to propose (a person or thing) as suitable or possible for some purpose.
3. (of things) to prompt the consideration, making, doing, etc., of.
4. to bring before a person's mind indirectly or without plain expression.
5. to call (something) up in the mind through association or natural connection of ideas.

RECOMMEND:
1. to present as worthy of confidence, acceptance, use, etc.; commend; mention favorably.
2. to represent or urge as advisable or expedient.
3. to advise, as an alternative; suggest (a choice, course of action, etc.) as appropriate, beneficial, or the like.
4. to make desirable or attractive.

Answer 2

These words are practically synonyms, but "suggest" suggests a proposal of possibilities, whereas "recommend"
indicates the preference of the speaker for one or more of the proposed items.

Answer 3

A recommendation is stronger and carries more of an air of authority than a suggestion.