---
title: "Understand the technology — Docs Segmentit"
description: "Masks, reconstruction and the difference between SAM 3 and SAM 3D."
lang: "en"
canonical: "https://segmentit.com/docs/technology/"
---

# Understand the technology

Masks, reconstruction and the difference between SAM 3 and SAM 3D.

## What is a mask?

A mask tells the editor which pixels belong to your subject. It separates the object from its surroundings so you can use it on its own.

## SAM 3 and SAM 3D

SAM 3 is Meta’s model for segmentation: finding and outlining subjects using text or visual prompts. SAM 3D Objects addresses reconstruction: estimating an object’s shape, texture and placement from an image and a mask.

## How can one photo become 3D?

The image provides visible shapes and appearance. A reconstruction model uses what it has learned to propose volume, including sides the photo does not show. Explore the result from different angles and adapt it to your creative project.

[SAM 3 · Guide and benchmarks](https://segmentit.com/sam-3/) [SAM 3D · Guide and benchmarks](https://segmentit.com/sam-3d/)