A 'keyword' is a term used in SEO to describe the phrases a customer uses when they search in Google.
For example, say I'm looking for someone to fix my boiler. I would likely search the term 'local plumbers' into Google.
Here the phrase 'local plumber' is the keyword I use when I search.
So, when picking keywords to SEO for your company, pick phrases that your customers will search to find a product/service/information like yours.