Terus terang selama ini saya masih bingung atau masih belum paham mengenai perbedaan antara ERC20 dan ERC223, saya sudah mencoba mencari di tread-tread yang sudah ada yang membahas mengenai hal itu. Tapi belum menemukan, mungkin ada suhu-suhu di sini yang paham dan mau membagi ilmu buat kita-kita yang masih awam soal ini. Sebelumnya terima kasih banyak saya ucapkan, salam bitcoiner 

(1) Eliminates the problem of lost tokens which happens during the transfer of ERC20 tokens to a contract (when people mistakenly use the instructions for sending tokens to a wallet). ERC223 allows users to send their tokens to either wallet or contract with the same function transfer, thereby eliminating the potential for confusion and lost tokens.

(2) Allows developers to handle incoming token transactions, and reject non-supported tokens (not possible with ERC20)

(3) Energy savings. The transfer of ERC223 tokens to a contract is a one step process rather than 2 step process (for ERC20), and this means 2 times less gas and no extra blockchain bloating.

Switching from ERC20 to ERC223

"ERC23 tokens are backwards compatible with ERC20 tokens. It means that ERC23 supports every ERC20 functions and contracts or services working with ERC20 tokens will work with ERC23 tokens correctly."

Sources: https://github.com/Dexaran/ERC23-tokens/tree/Recommended#erc23-token-standard (ERC23 and 223 are the same thing). To read the full discussion about ERC20 and ERC223, follow this link: https://github.com/ethereum/EIPs/issues/223