A call bear spread involves selling a call with a lower strike price and subsequently buying a call with a higher strike price. Both call options need to have the same expiration date.
The Max Loss is limited to the difference between the two strikes minus the net premium.
The Max Gain is limited to the net premium received for the position. I.e. the premium received for the short call minus the premium paid for the long call.
When to use: When you are mildly bearish on market direction.
A call bear spread is usually a credit spread. A credit spread is where the net cost of the position results in you receiving money up front for the trade. I.e. you sell one call option (receive $5) and the buy one call option ($4). The net effect is a credit of $1.
This type of spread is used when you are mildly bearish on market direction. Same idea as the Call Bull Spread but reversed - i.e. you think the market will go down but think that the cost of a short stock or long put is too expensive.