What are the differences between const and readonly?

const:

• const creates constants whose value doesn't change over time
• const variables are static by default
• variables are needed to be initialized and not assigned anywhere
• only ValueTypes can be made const variables

readonly:

• readonly creates fields whose value can be assigned only under constructor
• these are not static types
• these can be just declared, but can only be assigned in constructor
• readonly variables can be ReferenceTypes
• readonly variables can only Instance fields and can't be local variables