There are various materials that can be recycled, and each material has a different colour to appoint its container.

In Brazil there are the following eco points:
• Blue - paper / cardboard
• Black - wood
• Green - glass
• Orange - hazardous waste
• Yellow - metal
• White - waste clinics and health services
• Purple - radioactive waste
• Brown - organic waste
• Gray - not generally recyclable waste, mixed or contaminated and not possible to separate

Back in Portugal, there are only these:
• Blue - paper / cardboard
• Green - glass
• Yellow - plastic and metal
• Red - batteries
• Black - organic and / or any of the other

Note: currently there is, in large supermarkets, the electron point that serves to put the old appliances.

Source: wikipédia