The search button is your friend, what light is a very common thread topic.
What do you want the light to do primarily.
1) Help to make you seen by other road users or 2) to illuminate your way where there is no street or other lighting or 3) be so bright and powerful that the beam melts rocks and could burn a hole in the sun?
What is your budget? can you spend £3 or £300.
Do you have a preference for USB charged battery pack types that you can phone charge, the magischine (& copies) with the big 18650 battery packs or something that runs on readily available & easily replaced batteries you can carry with you or dynamo powered?
My preference for a good all-rounder front light is the Cateye Volt 300. Solid dependable build quality, USB charge big screw on battery unit with good.run time, dual steady/flash mode as well as just flash and various always on power setting, on full power it is good enough to see by as long as you're not riding very fast or doing Mtb black runs at night, Easy to clip on and off and.compact when carried off the bike & the mount is both good enough not to slip about and easily adjusted or realigned if you feel the need to. Approx £30-35.
A brighter version is available Cateye Volt 800 or the very similar Smart 700 (excellent to see by light and fantastic VFM at ~£30).
The Smart Lunar range are very good lights primary to help others see you.
Smart lights IMO have a decent but not brilliant mounting bracket. cateye's adjustable band type is far better.
There are a wealth of inexpensive, copies of good quality Magischine type battery pack and lamp units generally hiding under the CreeT6 heading, there are a few horror stories of incendiary battery packs but most people who have them seem very happy.
Have a search though on the relevant section of the forum. You'll find plenty of advice has already been given out.
