what's a good road bike for leisure? I wana ask you guys for some advise. Wish to buy a bicycle for my husband for Chritsmas. He sure did mention he would like a road bike and not a mountain bike.
He is 5'6 tall and weighs approx 170pounds.
I am confused about the frame size and the various options of brakes etc.
My budget is about 500$
Can you guys help me narrow down my search or throw in some names bike brands I can look for? Also which site is recommended? Or which store is better to go have a look? Would really appreciate your advise! Thanks
Today (2019) road bikes have branched into several sub types, each optimised for certain type of riding. Yet, several are quite versatile.

Road bikes for races stayed very much the same in their scope of use as they were in the past. Today they are specialised on aerodynamics and or lightness for climbs. These are hardly ever good beginner bikes. When you need one, you will know it already. People typically get them because they actually race, dream of racing, or are just in love with the bike.

Endurance bikes are a road bikes with a more relaxed geometry. That is, the rider is not so low and stretched out, and the bike is slightly less agile. These bikes now often come with disc brakes. Disc brakes allow wider tyres. A typical endurance bike ships 28 mm tyres, and is often good for slightly wider tyres. They are perfect for bound surfaces like tarmac. But also good for light gravel roads. Their disadvantage to race bikes are slower and usually heavier.

Gravel bikes continue this trend to even wider tyres and more stable geometry. With 40 mm wide tyres these bikes can be ridden on rather coarse gravel and easy trails. Some gravel bikes are almost as off-road capable like mountain bikes used to be in the 90s. Gravel bikes always have disc brakes. Their disadvantage compared to endurance bikes is higher weight, higher price, slightly slower.

There are categories like cyclocross, touring, and time trial, and tri-bikes.