Ancestry UK
*** Update January 7th 2025 - Exciting News! If you are a UK Ancestry subscriber, the 1921 Census is now abailable to view on Ancestry ***
In the UK, Ancestry has one of the strongest toolsets for family tree research. There's a massive data set including census images and information for all UK census years up to 1911, The 1939 Register as also included which gives a more upto date insight. Most UK parish records are fully documents, so Birth, Marriage, Death, Christing and Burial Records for many areas go back many generations.
There are also numerous collections of Military, Immigration, Emmigation, School, Courts, Financial, and linked faily trees form other members.
Ancestry DNA is also the biggest testing company in the UK. It gives you an excellent view of you likely Geographic origins, and shows for most people thousands and DNA matches to people who have been tested, from close relatives through to very distant.
Ancestry uses autosomal DNA testing which is particularly accurate for finding both close and distant relatives on your maternal and paternal sides.