You've never heard of them?! Ell, you have had a deprived childhood!
They are all children's TV programmes from the 1970s, which aired on UK TV, and are fondly remembered by many 30-something adults!
Clangers = Puppet creatures which lived in holes covered by dustbin lids on a planet. They were knitted, the sets consisted of lots of aluminium foil, they spoke in whistles, and there was a Soup Dragon. Maybe you shouldn't have asked.
Bagpuss = a cat soft toy. There was a little girl called Emily, and it was set in a toy shop. The toys came to life, and there were mice on the 'mouse organ', a scholarly wooden woodpecker called Professor Yaffle, a rag doll, and I can't remember anything else.
Roobarb and Custard = a cartoon with a cat and a dog. Just to confuse things, the dog (Roobarb) was yellow ie custard colour, and the cat Custard was pink (rhubarb colour).

The animation was weird and flickery, but it was cool. There was a voice-over by some British man, possibly Richard Briers (?).
Oh well, you had to be there I think!
