We know we can connect nouns with the と particle like so:
|Vegetables and fish and milk and water.|
But the repeated use of と becomes cumbersome when we need to enumerate a long list. We want to say “A, B, C, and so on”. In this case, we use the following structure with the particles や and など.
|A, B, etc.|
|I will buy a television, a fridge, and so on.|
Contrast this to the sentence which only uses と.
|I will buy a television and a fridge.|
|I will study mathematics and chemistry, etc.|
The object を is very often omitted when など is used.
|I don’t understand the difference wines and whiskies.|
とか is the casual way of saying the above. In fact, you will never heard や and など used in conversation (or, at least, very rarely). You will hear とか all the time. What makes とか particularly versatile is that it can be added to just about anything (や can only be used with nouns).
|I’ll buy milk and bread another things.|
|She was umming and arring.|
|A person called Iwasaki or something.|