Bots (short for “robots”) are automated software programs that perform tasks over the internet without direct, moment-to-moment human control. They execute predefined instructions repetitively and at speeds and volumes impossible for people, which makes them enormously useful – and, when misused, dangerous. Bots are a foundational concept in web and API security because so much internet traffic is automated rather than human.
Bots fall broadly into “good” and “bad” categories. Good bots perform beneficial, sanctioned work: search-engine crawlers that index websites, monitoring bots that check site availability, chatbots that assist users, and integration bots that connect services through APIs. Increasingly, AI agents that call tools and APIs on a user’s behalf are a fast-growing class of legitimate automation.
Bad bots are built or repurposed for malicious ends. They drive credential stuffing and brute-force attacks (feeding account takeover), scrape content and pricing, test stolen payment cards (carding), hoard limited inventory, create fake accounts, generate spam and fraudulent clicks, and participate in DDoS attacks. Large collections of compromised devices coordinated by an attacker form a botnet, providing the scale for high-volume campaigns.
A defining challenge of modern bots is that sophisticated ones deliberately imitate human behavior – rotating IP addresses, spoofing browser and device characteristics, mimicking realistic timing, and solving basic challenges – to evade detection. This makes telling human from bot, and good bot from bad bot, a central and difficult security problem.
APIs are especially exposed to bots because they are designed for programmatic access, so automated calls are expected and normal – which is exactly what malicious bots exploit to blend in. Managing bots requires behavioral analysis, fingerprinting, reputation checks, rate limiting, and machine learning to classify traffic accurately and respond appropriately, rather than bluntly blocking all automation.