I saw that we have write-ups for Google Adwords but nothing for Bing so here is a basic guide/faq. This is in no way meant to be a comprehensive answer to everything but answers to the questions I receive the most regarding Bing Ads:

I use Google Adwords, why do I need Bing?
Why use one search engine when you can use them all, more conversions = more money and Bing Ads CTR's tend to be a bit higher in my experience.

What is it?
Bing Ads is a PPC service that allows you to advertise just like Google Adwords.

How does it work?
Ads are displayed with user's search results based on the keywords they search or websites they visit and the content of these sites.

How do I determine my keywords?
Keyword research is similar to Google Adwords, you can research keywords with Bing's keyword tool or even have Bing scan your landing pages to find keywords on it's own.

What are negative keywords?
Negative keywords make sure that your ads don't get triggered on a search that may contain your keywords but isn't relevant to your ad.

Why isn't my ad approved?
Ads need to follow Bing's guidelines, if you aren't within these guidelines they may choose to not display your ad. Be sure to check your ads and landing pages to ensure that you are following the guidelines.

What are dynamic keywords?
Dynamic keywords allow you to have your ad change depending on the searcher's criteria, this allows more flexibility, impressions and clicks for you.

Can I optimize my ads?
You can optimize your ads to the fullest in many ways. Your ads can be displayed by customer demographics, location, time and even what devices they use. Ensure landing pages are optimized and test different keywords to improve your CTR and conversions.

Will I go over budget if my budget runs out?
No, once your budget has depleted your ads are no longer displayed.

Hopefully this helps answer a few questions, feel free to add anything that was left out.