Landing craft
The Fairmile H Landing Craft Support (Large) had armour added to its wooden hull and a turret with an anti-tank gun fitted. The LCS(L) Mark 1 had a Daimler armoured car turret with its QF 2–pdr (40 mm) gun. The Mark 2 had a QF 6–pdr (57 mm) anti–tank gun.
The American Landing Craft Support was larger, each was armed with a 3-inch gun (7.6 cm), various smaller guns, and ten MK7 rocket launchers.

Inflatable landing craft: Inflatable boats were often used to transport amphibious troops from high speed transports and submarines. The United States used a 7-man Landing Craft, Rubber (Small) (LCR-S) and a 10-man Landing Craft, Rubber (Large) (LCR-L).
The first and last instances of the large use of rubber boats in amphibious operations in World War II were the Makin Island raid in 1942 and the landing of the 1st Battalion 6th Marines Battle of Tarawa in 1943 where the Battalion commander Major William K. Jones was nicknamed "Admiral of the Condom Fleet".

Landing Craft Group and wartime training: After Pearl Harbor, the U.S. Army and Navy began intense planning for the transport of millions of men into combat and the training for amphibious operations. By June 1942, Amphibious Force, Atlantic Fleet (AFAF) established headquarters at Norfolk (Virginia) under the command of Admiral Henry Kent Hewitt. Temporary headquarters for a transport command were set up in an old American Export Line transport ship that had been built for the Army in World War I.: 66–67  Within the transport command, a Landing Craft Group was created to prepare the crews of landing ships.
"The training of landing craft crews under the direction of Captain W.P.O. Clarke began at the end of June 1942," according to Naval historian Samuel Eliot Morison. Clarke was given orders to "secure, organize, and train crews for approximately 1,800 landing craft" including LSTs and LCIs, which at that time were still in the design phase.: 70 
To man and support such landing craft, the Navy ordered that 30,000 men and 3,000 officers be trained in a matter of months, but initially the Landing Craft Group consisted only of Capt. Clarke, two officers and a yeoman. In creating training programs, Clarke studied blueprints for the new craft and "from these paper drawings he prepared ship's organizations for each type. This was the first textbook for crews assigned to the large landing craft. From this, they were to be trained in what their duties were to be, what the ship would be like, and how it would be expected to operate.": 67 
In August 1942, Capt. Clarke was told about Operation Torch and secret plans to invade North Africa the following November. He had only a few months to train thousands of men, most of whom were just out of indoctrination school. "They were the butchers, the bakers, and the light bulb makers of American youth. War was new to them, and organized Navy life was strange," observed Lt. Eric Burton, a Naval officer who wrote By Sea and by Land, a semi-official account published during the War about amphibious combat.
Capt. Clarke created hydrographic, maintenance, medical, and communications training programs, and a section to train Army shore parties how to unload landing craft. He set up a training facility at Solomons Island, and held exercises on the shores of the Chesapeake Bay around the clock, day and night.
On 1 September 1942, the Amphibious Force and its Landing Craft Group rented the Nansemond Hotel, a popular resort hotel on Virginia Beach near Norfolk, to use as a headquarters building. Eventually, 40 major amphibious operations would be planned at the old hotel. For several weeks, Gen. George S. Patton worked on plans for the invasion of North Africa out of the Nansemond.
"Captain Clarke had less than two months, about one-third of what had been considered the minimum, to train these men to conduct night ship-to-shore landings," wrote Samuel Eliot Morison about the preparations for Operation Torch. "Considering the time limitations, his performance was remarkable." Clarke was awarded the Legion of Merit for the accomplishment. According to the Presidential citation, he and the Landing Craft Group "brought these ships and craft to a high state of readiness for combat operations in all subsequent major amphibious operations in the Atlantic, Pacific, and Mediterranean theatres.

Early Cold War developments: Despite all the progress that was seen during World War II, there were still fundamental limitations in the types of coastline that were suitable for assault. Beaches had to be relatively free of obstacles, and have the right tidal conditions and the correct slope. However, the development of the helicopter fundamentally changed the equation.
The first use of helicopters in an amphibious assault came during the Anglo-French-Israeli invasion of Egypt in 1956 (the Suez War). Two British light fleet carriers were pressed into service to carry helicopters, and a battalion-sized airborne assault was made. Two of the other carriers involved, HMS Bulwark and HMS Albion, were converted in the late 1950s into dedicated "commando carriers".
The US Navy built five Iwo Jima-class landing platform helicopter vessels in the 1950s and 1960s, and various converted fleet and escort carriers for the purpose of providing a helicopter amphibious assault capability. The first of the type envisaged was the escort carrier USS Block Island, which never actually saw service as an amphibious assault ship. Delays in the construction of the Iwo Jima class saw other conversions made as a stopgap measure; three Essex-class aircraft carriers (Boxer, Princeton, and Valley Forge) and one Casablanca-class escort carrier (Thetis Bay) were converted into Boxer and Thetis Bay class amphibious assault vessels. Helicopter amphibious assault techniques were developed further by American forces in the Vietnam War and refined during training exercises.

Current landing craft: 

Amphibious mechanized utility and landing craft: Mechanized utility and landing craft were the kind used during the second world war and, while the mechanized landing craft of today are similar in construction, many improvements have been made. For example, landing craft (such as the LCM-8 of the US Navy) are capable of a military lift of 183 metric tons (180 long tons) at a speed of 22 km/h (14 mph), carrying even heavy equipment, such as M1 Abrams tanks. Landing craft can mount several machine guns or similar weapons for the defense of troops and/or vehicle crews inside.

Air-cushioned landing craft: The air-cushioned landing craft (Landing Craft Air Cushion, or LCAC in the US Navy) is based on small to mid-sized multi-purpose hovercraft, Also known as "over the beach" ("OTB") craft, they allow troops and material to access more than 70 percent of the world's coastline, while only approximately 15 percent of that coastline is available to conventional landing craft. Like the mechanized landing craft, they are usually equipped with mounted machine guns, although they also support grenade launchers and heavy weapons. These vehicles are commonly used in the United States Navy, the Royal Navy, the Russian Navy, and the Hellenic Navy.

Landing barges: Landing barges were adaptations of British Thames barges and lighters as landing craft. In size, they came between the landing craft and landing ships. They were used at all beaches during the landings at Normandy and were manned by British crews.
Some were fitted with engines, while others were towed to the beach. They were used for defence, transportation, supply (food, water and oil) and repair (fitted out with workshops).
Those fitted for vehicle carrying had a ramp fitted in place at the rear and they had to back onto beaches. They would work from ships and coasters to the shore and back.
Two flotillas were made up of "flak barges" to provide defence of the beaches. Like landing craft, flak barges carried A/A guns: two 40 mm Bofors and two 20 mm Oerlikon, with army gunners and naval crew.
The Landing Barge, Kitchen (LBK) was fitted with a large superstructure containing the galley. With a crew of 20 plus, they could carry food for 800 for a week and provide 1,600 hot and 800 cold meals a day, including freshly baked bread.

See also: Balikpapan-class landing craft heavy
LCM-1E
Mark 8 Landing Craft Tank
Ramped craft logistic

Notes: 

References: Navy Fact File: Landing Craft, Air Cushioned Archived 21 December 2007 at the Wayback Machine
Landing Craft Infantry (LCI) Assn. (usslci.com)
NavSource.org Landing Craft Infantry (LCI) Data and Photo Index
USS Rankin (AKA-103): Her Landing Craft
Hersey, John. "U.S.S. LCI 226". Life, March 27, 1944, pp. 53–61.