Table salt is refined sodium chloride and is available in a container, often a cylinder, with a pour spout on the top to fill your salt shakers.
Salt is a mineral needed by humans to continue living, and many times the manufacturers add in a bit of iodine to cover that essential mineral. You can purchase it with or sans iodine.
Table salt is plentiful and available all over, including fast food restaurants. The problem with this is that folks tend to go overboard, especially with traditionally salty foods like French fries.
The sodium in salt has a recommended maximum for daily consumption: between 1.5 and 2.3 grams, which is less than a tenth of an ounce. That's a large portion in one of those little salt packets at McDonalds. Factor in the food is usually salted during the cooking process and meats already contain salt direct from the animal and one can see it's easy to exceed the recommendations.
All food salts, when taken to the extremes of many first-world country diets, can lead to high blood pressure and cardiac issues. Yes, it's as serious as a heart attack. Watch your sodium intake like you do calories. If your blood pressure is creeping up as you age try cutting back on adding extra salt to your fries. Your heart will thank you when you reach 56.