You might have discovered a small egg sack near your windows or doorframes. This could be full of hundreds, if not thousands, of baby spiders that can hatch at any moment. If not dealt with, you'll have to handle a full-blown spider infestation. If you're removing the egg sack yourself, take care not to damage the sack, as you could disturb the baby spiders. Take a piece of kitchen roll and carefully dislodge the egg sack. Place the kitchen roll and the egg sack into a bin bag and tie the handles securely. Dispose of the bin bag in your general waste. You could also use a vacuum to dislodge and suck up the egg sack, but the sack might burst inside of your vacuum.