What is squamous cell vs basal cell skin cancer?

Different cell types: Squamous cell carcinomas are worse than basal cell carcinomas. Squamous cell carcinomas can metastasize where as basal cell carcinomas very rarely do. Both types occur more in sun exposed areas.

Different growth: Basal cell skin cancers often grow deeper and more destructive when left untreated causing large ulcerated areas. Squamous carcinomas more often spread radially and have a higher risk of spread to other organs if left untreated.

Both are NMSCs: Both are types of non-melanoma skin cancers (nmsc). Basal cell carcinoma (bcc) are the most common types of skin cancers. Bcc occur on sun exposed areas, are slow-growing, rarely spread, but can be locally destructive. Sqamous cell carcinoma (scc) usually start from sun-induced precancerous lesions (actinic keratosis) and then can progress to invasive tumors with risk of spread. See doc if worried.