Newby to i Mac

Hi, just took ownership of a 27 inch i Mac. Looking good so far. !st question of many. Is there a way of temporary closing down the mac without losing my data or open website windows. Tried sending it to sleep but closes everything down that's open. Is there a feature like windows ctl-alt-del that locks it so no one can access it. I have already set up a password for when it does go to sleep, and start up.

Just need a way of quickly locking it and return 10 mins later without losing everything I had open.

Thanks

Sleeping it shouldn't close down anything - it will operate exactly as you've described. You can also just sleep the monitor with cntrl-shift-eject

Sleep should not close anything down. It just saves everything in its current state and goes into a low-power mode. When you click the mouse or touch a key, it should wake right up with everything just as you left it.

In System Preferences, there's a Security section where you can set your iMac to require a password upon waking up from sleep. System Preferences can be accessed from the Apple menu that's always at the top left of your menu bar.

Thanks for that. Job done.