Please keep it in a safe place! Now you may deposit any amount, exchange currency, change the cheque number (useful if you got this cheque as a payment from a 3rd party and want to be 100% sure in further operations confidentiality), or split any amount from the cheque or withdraw cheque amount in any convenient way.
For your enhanced confidentiality, the page contents will be lost after reload, to re-open the cheque you will need to enter a cheque number again.