Yep, Christiaan’s using our best friend: Investopedia. Love it.
The bodies are the open and close. Up candles have a lower open but higher close. Down candles have a higher open but lower close. “Wicks” (the lines) are the highs/lows of the day.
I use candlestick charts because line charts ignore the highs/lows of the day and mainly focus on tracking closing prices.
Bar charts, just don’t attract the eye for me, like candlesticks do.
A candle is the open, high, low and close prices during the period. On a daily chart, that’s the open, high, low and closing price for that day. On a weekly chart, it’s the open, high, low and close for that week. An hourly chart would be the open, high, low and close, prices for only that hour. A new candle would be created each hour.
Additionally, there are all sorts of patterns among candlesticks that give their own insights. Not that you have to delve into it that far. But just realize that’s a benefit of candlesticks over bar charts or line charts: https://www.google.com/search?q=candlestick+patterns&tbm=isch&chips=q:candlestick+patterns,g_1:cheat+sheet:DE87h3ZYqdk%3D&hl=en&sa=X&ved=2ahUKEwjy14Xf6dXsAhVGQKwKHSqjBmMQ4lYoAHoECAEQGQ&biw=1746&bih=852