Snap.do Smartbar is a browser extension that offers features like screen capturing and social media shortcuts but can also display intrusive pop-up ads and redirect searches. While it may be installed intentionally during other programs' installations, its removal is complicated as affiliated files may remain and pop-up ads can still occur without a full system scan to restore default browser settings and safeguard the system. Snap.do itself may not be malicious but users should be cautious of potential data collection, so it is recommended to remove it if unwanted.