trafficsource

A traffic source, or trafficsource, refers to the origin of visitors to a website. In web analytics, it is a classification used to identify where users came from before arriving on a site. Understanding traffic sources helps site owners assess the effectiveness of marketing channels and user acquisition strategies.

Common traffic sources include direct visits, organic search, referrals from other sites, social media, paid search, email campaigns, and display advertising. Analytics tools assign each visit to a source, often using UTM parameters (utm_source, utm_medium, utm_campaign) or browser referrals, to attribute traffic to the correct source. The classification may also be refined by channel, medium, and campaign.

Attribution models determine how credit for a conversion is assigned to sources. Models range from last-click to first-click, linear, and time-decay, and many analytics systems support multi-channel attribution. Data can be affected by cross-device usage, multitouch customer journeys, ad blockers, and privacy restrictions that limit cookie access.

Practical use: marketers monitor traffic sources to compare channel performance, optimize SEO and content, allocate budgets, and tailor messaging. Direct traffic represents users who enter the site URL directly, while organic search traffic comes from search engine results, referrals from other sites come from backlink referrals, social traffic from social networks, and paid traffic from paid advertising.