Orders, Decorations and Medals are usually awarded by a Government. Orders are lifetime titles that cannot be passed down whilst Decorations and Medals are awarded for a specific act(s) of service or achievement. Orders are typically for significant service to the country whilst Decorations and Medals are given for gallantry, meritorious service or achievement.
Orders
In the UK these are usually Orders of Knighthood which are then split into different degrees for different levels of achievement or service. Currently they are awarded in the New Year’s Honours or Birthday Honours lists. They include the Order of the Garter, Order of the Thistle, Order of the Bath, Order of Merit, Order of Saint Michael and Saint George, Royal Victorian Order, Order of the British Empire, Order of the Companions of Honour, the Distinguished Service Order and the Imperial Service Order.
There were some other Orders but they generally relate to British India so they are now Dormant.
Decorations
These are generally given for acts of outstanding bravery. They include the Victoria Cross (VC), George Cross (GC), Conspicuous Gallantry Cross, Royal Red Cross, Distinguished Service Cross, Military Cross, Distinguished Flying Cross, and the Air Force Cross.
Traditionally, other than for the most senior of the Crosses (the VC and GC) officers were awarded a Cross and Other Ranks received a similar ranking Medal. Examples are the Military Cross and the Military Medal. Since the 1990s this distinction has been removed and now both officers and other ranks can receive the Cross version. This “status distinction” is often encountered in WW1 / WW2 groups.
Medals
Some Medals were given for acts of bravery as noted above but the Cross / Medal “status distinction” was phased out in the 1990s. Medals for gallantry and distinguished conduct are senior whilst other medals are given for campaigns (taking part in a military campaign), Polar Medals (for activities in those regions), Valuable Service, Jubilee / Coronation / Durbar, and Efficiency / Long Service.
Foreign Awards
Often Foreign Awards are present in British groups and they can be awarded for a variety of reasons. However, the recipient needs “Permission to Wear” them if they want to integrate them into a British medal grouping. This Permission is not always granted so the Foreign award may be separate to the rest of the group.